I'm always intrigued when two movies from essentially the same genre and made within a couple of years of each other get off to an oddly similar start, particularly when one of those films makes a big splash and the other sits comparatively in the shadows. In Jordan Peel's belting 2017 debut Get Out, mixed-race couple Chris and Rose are driving along a quiet country road to a social gathering and come to sharp halt when their car hits a deer, which is not killed outright by the collision. In Karyn Kusama's 2015 The Invitation, mixed race couple Will (Logan Marshall-Green) and Kira (Emayatzy Corinealdi) are driving along a quiet country road to a social gathering and come to a sharp halt when their car hits a coyote, which is not killed outright by the collision. In both cases the sight of the wounded animal has a profound effect on the individuals in question, and the incidents strongly resonate later in both films. Where the two titles significantly differ is that while in Get Out the pairing of a black male with a white partner is used to explore issues of race and prejudice, in The Invitation it is one of two relationships (one mixed race, one gay) employed to quietly establish that prejudice is not part of this story's game plan.

The social function to which Will and Kira are driving is a dinner party being thrown by Will's ex-wife Eden (Tammy Blanchard) at the house in which she and Will used to live, a party to which she has also invited a selection of their old friends. Will is apprehensive about the whole thing, and with good reason. Two years previously, he and Eden split up following the accidental death of the their young son, after which Eden effectively disappeared. Now she has unexpectedly resurfaced with her new husband David (Michiel Huisman), and Will has since moved on and is clearly concerned that returning to the house and seeing Eden again might open up old wounds. When he arrives, however, he is greeted warmly by everyone, but despite the convivial atmosphere, he cannot shift the feeling that something is decidedly off about this gathering.

That, in effect, is the setup and as much as you need to know before sitting down for what for me was one of the cinematic highlights of 2016, but one that has required some hunting out for non-Netflix subscribing UK residents and has taken its sweet time to land a Blu-ray release here. I'm thus not going to go on a  spoiler binge (the less you know about what unfolds the better), but do feel the need to discuss a plot point that is hinted at strongly before it is revealed, one that occurs early enough not to count as a surprise twist. If you do want to go in completely cold, however, I'd still give the paragraphs in question a miss. Worry not, an appropriately placed warning will be given.

The Invitation is one of those rare films that I knew I was going to like just a couple of minutes in. Sometimes I can't quite put my finger on just what it is that grabs me so quickly and completely about a film's opening scene, and I suspect that it's a personal thing, a subconscious response triggered by a combination of elements that just click for me. The most recent example of this was probably Lynn Ramsay's You Were Never Really Here, where the editing and sound design of the opening shots proved strangely seductive even before a whisper of the story was revealed. Here it's the low-key subtlety and believability of the conversation between Will and Kira as they drive, and just maybe the fact that Will is presented not as the studio standard clean-cut lead, but a damaged man who almost seems to have taken emotional refuge behind his long hair and full beard.

From the moment they arrive at his former home there is a pervading sense that something is amiss, yet what is and continues to be uncertain is whether this sense of foreboding is a product of Will's still troubled mind. As he walks in, he experiences a flashback to happier times when his child was still alive, and it won't be the last. Then there's Sadie (Lindsay Burdge), a scantily clad woman who eyes him up seductively from the kitchen. Is she real? Apparently so, a friend of Eden and David's who is staying with them and helping them out, whatever that means, and whose behaviour provides the first clue to where the story is soon to head. Both Will and Kira are warmly greeted by people that Will has not seen for some time. They're all then introduced to Sadie, and a short while after, Pruitt (John Carroll Lynch, probably the most recognisable face in the cast), another friend of Eden and David's, turns up at the door, and after being introduced tends to just sit watching on silently from the background. When he does elect to speak, he has a story to tell that also proves a signpost to where things might later head.

The conversation is cheery and the atmosphere relaxed, but Will never seems completely at ease in company that he would once have cherished. From the off, we're steered subtly into seeing things from Will's point-of-view, in part through the low-key naturalism of Logan Marshall-Green's performance, which renders his increasing unease relatable to anyone who has found themselves in a social situation where they've endured discomfort rather than break an unspoken social contract and be thought impolite. Underlining this are the discordant chimes and whines of Theodore Shapiro's score, which creeps unsettlingly onto the soundtrack to seemingly give weight to Will's conviction that something is askew with an evening that on the surface is nothing but good company and cheerful discourse.

It's then that David asks if he can show his guests something, and I now feel obliged to give my promised spoiler warning. Because of the manner in which this plot point is signposted and the early stage in the narrative at which it occurs, I'd argue that it does not constitute a major spoiler, but if you want to go in unprepared and work it out for yourself then skip to the final paragraph or click here to have your browser of choice do it for you.

What the smiling David shows his guests is a promotional video for a group that he, Eden, Sandy and Pruitt are members of, one known as The Invitation (yes, the title has a double meaning here) that I would have no problem whatsoever describing as a cult. Now the reason I claimed this was not a big spoiler is that there are pointers to this revelation from an early stage, particularly the presence and behaviour of Sandy and Pruitt, not to mention Eden and David's ever-present Cheshire Cat smiles. What did catch me out is that this is not played as a surprise twist but is matter-of-factly introduced in a manner that acknowledges we will have likely picked up on those earlier clues. What is uncertain is how this information is destined to impact on the evening and the group of friends. Is it an ominous portent of impending conflict to come or merely an admission on the part of Eden and David of the root of their new-found happiness? The promotional video certainly creeped me out, but this sort of smiley claptrap always has that effect on me, though considering this one includes footage of a woman dying and her fellow cult members embracing her spirit, it's not surprising that the guests have a similar reaction. When David tries to convince them of the positive impact The Invitation has had on him and Eden by using Will's grief at the loss of his child as an example, however, he touches a nerve, upsetting and even angering Will, who by this point has become even more convinced something is seriously fucked-up about this gathering.

It's then that David suggests they play a game of "I want" that he claims will put into practice some of the things he and Eden have learned, and I was absolutely with Will in his distrust and by then mentally urging him to get the hell out this house. Indeed, one of his friends, Claire, at this point decides to do exactly that due to her extreme discomfort at where the evening is heading. David smilingly attempts to discourage her but when Will intervenes, any objections to her departure are dropped and off she goes. When Pruitt reveals that he needs to move his car because its blocking her vehicle in, however, a suspicious Will immediately positions himself by the window to watch their every move. Everything appears to be above board, and though the two do slip out of his line of sight for a few seconds, Pruitt quickly returns to the house in good cheer. Even if he was up to no good, Claire was in her car by the time the two disappeared from view and Pruitt couldn't have done anything to her in such a short space of time. Could he? By this point Will's discomfort has evolved into what could very well be paranoia. His friends certainly do not share his suspicions and they all come across as decent, level-headed people. Could they just be that blind to what's going on, whatever it is? Or are we observing events exclusively from the viewpoint of man who is in the early stages of an emotional breakdown triggered by his return to the scene of the most traumatic event of his life?

The Invitation is an object lesson in how to do slow-burn thriller right. It hooks from its opening scene, not with an attention-drawing bang but by presenting us with sympathetic characters who feel completely grounded in reality, and by building an atmosphere on unspecified discomfort that evolves into fearful dread. It cleverly and effectively plays with the notion that Will's unease may simply be a paranoid symptom of his suppressed grief and extreme discomfort at Eden and David's new life choices, even if we're more naturally inclined to side with his conviction that something is very wrong than admit that we have become complicit in a paranoid delusion. It's a point on which Kusama and scriptwriters Phil Hay and Matt Manfredi keep us guessing, and they are even able to effectively wrong-foot us at one stage, with the validity of evidence supporting Will's position kicked from under his and our feet just seconds after it has been angrily presented. It's a film that requires patience from its audience but rewards it in spades, not least in a nail-chewing climax that initially steers us in one direction, then redirects our attention only to do an about-turn and kick off for real in a manner that is genuinely startling. The performances are first-rate, the atmosphere treacle-thick, the direction confident and purposeful, and the score and sound-design are deeply unsettling. The Invitation was one of my picks of 2016 and three years on I absolutely stand by that decision. It steadily builds tension and delivers a gut-punch of a climax (one with troubling real-world associations) and a belter of an ending, one that in the spirit of the film doesn't shout but whose whispers have an almost apocalyptic sense of scale.

On paper, at least, The Invitation presents a challenge for any disc transfer, being set almost completely at night in rooms lit by lamplight and colour timed to give it a strong earthy hue of the sort we tend to associate with artificial light (it's not how the human eye sees it, but how it photographs if your camera is balanced for daylight and is often used in films to signify that we're indoors at night). More naturalistic colour is used in the flashbacks and there is a blue hue to sequences that take place in the garden. Yet even with this in mind, the 2.40:1 1080p transfer here is spot on. Just occasionally the black levels soften a tad, but for the most part they are solid and the contrast as a whole is pleasingly balanced, with the sometimes deep shadows appropriate for the setting and lighting conditions. The picture is sharp and the detail crisply rendered, and given that the film was probably shot digitally, the complete absence of dirt and damage is to be expected, as is the lack of grain. And while the grabs here do make the image look dark, on a correctly calibrated TV there are no clarity issues.

There are two soundtracks available, DTS-HD Master Audio 2.0 stereo and DTS-HD Master Audio 5.1 surround. I can't say for certain what the original mix was, but can't help but suspect the stereo track was downmixed from the 5.1 for people watching the film on their phones (oh for heaven's sake don't), as while both are clear and free of issues, the surround track blows the stereo out of the water, being considerably louder with a far brighter and fuller feel to the dialogue and music. This is absolutely the go-to track for a film whose sound design is so much part of its texture.

Optional English subtitles for the deaf and hearing impaired have been included.

Commentary with Director Karyn Kusama and writers Phil Hay and Matt Manfredi
Three of the principal creative forces behind The Invitation share useful details about the making of the film and memories of the shoot, as well as discussing in some detail the underlying themes and how they are explored, something I daren't elaborate on for fear of dropping spoilers. More than once we're told of scenes that were cut down from their scripted version in order to infer what was originally more openly stated, including one that would have confirmed something that remains more effectively ambiguous in the film. It's here that I learned that it was shot primarily in an actual house and that the windows were tinted to allow most of the filming to take place during the day, and that the two days of rehearsal they took is nowadays considered a luxury for any production, particularly one this small. Kusama identifies an influence of Kurosawa's High and Low on some of her framing choices, and she has some really interesting insights into her approach to the shooting and staging of individual scenes.

The Making of The Invitation (10:01)
A slick promotional video for the film that is snappily shot and edited – complete with eye-catching transitions, filtered imagery and a bouncy score – in what is almost the polar opposite approach to that taken by Kusama for the film itself. It's made up of a blend of cast and crew interviews and behind-the-scenes footage, some of which contains potential spoilers for newcomers. Actually, that spoiler warning goes for every special feature here.

Going Back Home – an interview with Director Karyn Kusama (33:46)
A welcome interview with director Kusama, who outlines how she came to this direct this project (there is one factor oddly not mentioned here – see the interview with the scriptwriters below) and why she was drawn to it, and she talks about the challenges she faced and her approach to telling the story cinematically following her decision to frame events from Will's point of view. We learn that cinematographer Bobby Shore took inspiration from Gordon Willis's work on Klute for the film's look, that it was edited in Kusama's garage at the height of summer, and that lead actor Logan Marshall-Green saw his beard as having the very narrative purpose that I suggested above, though producer Nick Spicer has a different take on this (see below).

There is Nothing to Be Afraid Of – an interview with Producer Nick Spicer (20:08)
The film's enthusiastic producer Nick Spicer kicks off with some info on his production company XYZ Films, then talks about teaming up with Karyn Kusama, the casting process, cutting the original budget of $5 million down to just over $1 million, shooting most of the film in a single location in a schedule of just 20 days, and the deal they struck with Netflix that also allowed for the distribution of the film on alternative platforms, hence this Blu-ray. He also suggests that the reason actor Logan Marshall-Green was sporting a thick beard is that he had grown it for another film he was working on at the time and that it had to stay if he was to play the role. I have no doubt this was the case, but I still prefer the justification the actor gave the director for its presence.

Tonight's the Night – an interview with writers Phil Hay and Matt Manfredi (20:20)
Scriptwriters Phil Hay and Matt Manfredi recall how they met and why the script for The Invitation had a ten-year gestation process, how the experience and the processing of grief helped shape the story and why the $1 million dollar budget and total creative control was ultimately just right for the film. They perceptively explore an aspect of the story that I can't discuss without delivering spoilers, confirm that they were very happy with how the film turned out and that they can't imagine now how it would have looked had they directed as originally planned, and reveal that one of the reasons that the script landed on director Karyn Kusama's lap is that she and Hay are married. Ah, not quite the chance event I thought, then.

Playing Sadie – an interview with Actor Lindsay Burdge (15:02)
Energetically upbeat actor Lindsay Burge recalls landing the role of Sadie after a meeting with director Kusama and being drawn to it without having read the whole script – once again, I can't say more on this without revealing plot elements that shouldn't be known in advance, but the story is entertaining. She seconds comments made on the commentary about how two days of rehearsal is a luxury these days (is it me, or does that seem mad?), likens shooting in a single location with a good group of people to a theatre production, and remembers it as one of the best experiences she's had on a film set. Her reaction to watching the finished film for the first time is also rather fun.

How refreshing it is to watch a thriller that takes its time and builds tension through inference rather than shouting at the audience, and when the payoff comes, it proves absolutely worth the wait. The Invitation is not for everyone, and the difficulty of selling it to thriller fans is that the elements that would act as the best hook are the ones you shouldn't reveal to those who've never seen it, as the mystery – and indeed the question of is there really is a mystery – is central to what makes the build-up so effective. Second Sight have done a sterling job here, with a fine transfer backed by an excellent set of special features. Highly recommended.