Thirty-something Len Lewin is a film industry electrician who sidelines at a local theatre. He and his actress wife Joy have two kids and appear content in their marriage and home life. Then one evening after a stint at his theatre job, Len offers to walk young actress Val to the tube station, persuading her to stop off for a drink on the way. The two immediately hit it off, and due to the late hour Len accompanies Val back to her front door. Their friendship continues to develop en route, and at journey's end Len jokingly plays for a kiss, and gets it.

When the pair next meet, Len asks for a second date and is invited by Val to a crew party being held the following evening. All appears to be progressing well until the next day, when Val arrives at the theatre in her school uniform and reluctantly admits she's not yet sixteen. Len is understandably rattled, but Val is keen for their still burgeoning relationship to continue. In spite of the risks, Len accompanies her to the party, and the two soon find themselves in too deep to quit.

Age-gap movie relationships are not uncommon, particularly between older men and younger women (funny how the reverse still seems almost taboo) – Clint Eastwood even directed one back in 1973 starring William Holden and Kay Lenz (Breezy, in case this one slipped you by). But stories in which the younger party is what we tend to regard as under-age are somewhat rarer. Lolita is the sub-genre's notorious grandfather, but over time that title has become associated more with child pornography than the celebrated prose of Nabokov, and any attempt to explore such a relationship on film has usually landed the filmmaker smack in the centre of a moral minefield. With that in mind, the balancing act performed by the little seen 1969 British film All the Right Noises is nothing short of miraculous.

Certainly director Gerry O'Hara doesn't play it safe with the casting, with Val played by 16-year-old Olivia Hussey, fresh from her work on Franco Zeffereli's Romeo and Juliet and whose cheery self-confidence genuinely deflects from her early teen looks. But while the couple's relationship is the central issue here, the age (and indeed social) gap between them is not, only intermittently rearing its head to prompt caution and considerable pause for thought at points of progression that in other circumstances would develop naturally. This is most keenly felt when they first spend the night together, an event that is carefully planned and hesitently approached, and whose sense of mutual innocence – both are in virgin territory here, so to speak – is preserved by O'Hara's smart decision to show nothing of the act itself.

This is, in essence, a love story with barriers and complications rather than a moral tale, one in which O'Hara observes his characters and explores their emotions rather than passing judgement on them. It's an approach that succeeds because right from the first scene everything about the characters and the situation feels authentic. The anchor point here is Len himself, an unpretentious, easy-going and instantly likeable working man whose attraction to Val may prompt disapproval from the more saintly audience members, but should spark a twang of self-recognition in anyone who has made that special and unexpected connection with someone other than their partner and secretly wondered what would have happened if, just maybe...

That this particular story of secret love hits a couple of 60s kitchen sink touchstones – an unexpected pregnancy, talk of abortion – is perhaps unsurprising, but both are handled with a refreshing lack of the usual dramatics, with Val and Len both blaming themselves rather than each other and the situation quickly accepted as something they have to live and deal with. The close calls to discovery are also there, from the lipstick on the collar to Joy's unexpected return to the flat in which Len and Val have just spent their first night, but the low-key handling and avoidance of melodrama ensures that both scenes play out how you would expect them to in real life rather than dramatic fiction. Such naturalism is evident in even the smallest detail: in the chemistry and body language that completely sells the rapid advancement of Len and Val's friendship as they chat in the pub; in the concealed guilt that prompts Len to resist his wife's advances and then recall the first kiss from Val when he finally submits; in the sudden release of passion after getting caught in the rain (an old favourite, but very well handled); in Val's guarded jealousy of Len's unbroken attachment to his wife; in the gentle secrecy of their efforts to spend time together.

Absolutely key to why this all works as well as it does is down to O'Hara's deft direction and a script (also by O'Hara, from his own novel) that doesn't strike a single false note, having neither the performed artificiality of scripted dialogue nor the the sometimes unfocussed looseness of improvisation. Yet somehow it always feels real, but in a manner that is never allowed to meander or lose direction. A string of perfectly judged and believable performances by an absolutely spot-on cast really sell it, and excellent though both Olivia Hussey and Judy Carne are as Val and Joy respectively – and they really are – it's Tom Bell's turn as Len that quietly and, given his pivotal role in the drama, rightly steals the show.

Let's talk about Tom Bell for a second. Although, one of the finest stage and screen actors this country has ever produced, he never achieved the star status that some of his contemporaries enjoyed, and became known primarily as a character actor who specialised in seedier roles, though his chiselled looks and aura of held-in-check aggression were key to two of his best remembered TV roles, as Frank Ross in the 1978 crime drama Out and Sgt. Bill Otley in the Prime Suspect series. And yet here is the Bell that should have been snapped up for lead roles, his everyday looks and easy and naturalistic way with dialogue making Len feel like the real deal, not the angry young man of Finney and Courtney, but a working Joe who is comfortable with the routine and trappings of family life, but still as vulnerable to temptation and the unpredictable rules of attraction as, well, any of us.

All the Right Noises is one of the most worthy inclusions yet in the BFI's Flipside strand, a little seen but exquisitely judged age-gap romance that makes you wonder why director O'Hara is not more widely written about and discussed, so finely balanced is his direction of performers and camera alike. Even the songs by once popular folk singer-singwriter Melanie seem well selected – they may ground the film in its time as surely as the hairstyles, but their melancholic strains function almost an expression of the characters' uncertainty and concerns for their own future happiness. What in lesser hands would have been played for its sensationalism is stripped of its potentially salacious overtones in order to focus on the characters and their feelings for each other, and how their actions might ultimately impact their individual concepts of normality. It's a lovely little film whose attention to realism and detail make every feel rich far beyond the deceptive simplicity of its story.

Having only recently stated that the BFI's Flipside titles were setting the standard for digital transfers of small scale British films of years past, I'm forced to backtrack a bit here, but with qualifying reasons. Certainly if you come to it from the pristine glories of Man of Violence then your first impression is of All the Right Noises is likely to be one of disappointment. The detail is fuzzier, the grain far more visible and there's a sometimes pronounced green tint to much of the imagery. This, I'll wager, is one time where the DVD looks almost identical to the Blu-ray. But before I go pointing fingers at the transfer, it's worth noting that much if not all of the film was shot on actual locations in sometimes low light, including scenes on the London underground and a park exterior at night. Back in 1969 I'll wager that even the fastest colour stock had to be pushed (a process of upping the film speed and then compensating in development) to shoot in such conditions without supplementary lighting, which on fast colour stock of the period would have resulted in just the sort of visual compromises evident here. Certainly the BFI's own accompanying booklet remarks on the source print's 'inherent green hue', and given the impeccable quality of other transfers in this series I'm going to make a small leap of faith and assume that this is as good as the film is likely to look. It's certainly been cleaned up to remove dirt and damage, and to be honest the grittier look rather suits the film's almost documentary-like approach to its storytelling.

The 48K/24-bit PCM mono soundtrack is a similar story, cleaned up to remove any damage or background hiss, but inevitably still restricted in its dymnamic range. Given the almost documentary nature of some scenes, the dialogue is always clearly audible and very little distortion is evident, even on the music.

The Spy's Wife (1972) (28:07)
An enjoyably whimsical short with British sex farce overtones, directed by Gerry O'Hara and starring Tom Bell, who plays a British spy (named, perhaps a little unimaginatively, Tom) who nips off on a mission to Prague, leaving his wife Hilda (Dorothy Tutin) to carry on her secret affair with his Czech counterpart (the inimitable Vladek Sheybal). Their tryst is repeatedly disrupted, however, first by Tom's parting suggestion that their flat is bugged, then by a pair of unexpected visitors, but unbeknown to Hilda, Tom has his own mysterious rendezvous to keep. Insubstantial perhaps, but well made and rather fun, particularly in its refusal to reveal the full extent of just what's going on until the final scene. The cast are a key draw – Sheybal can communicate so much with just a silent, mournful look – but I'm still not sure who those two blokes were who turned up at the flat looking for Tom. The image is sharper and has better colour than the main feature, but exhibits considerably more damage.

Olivia Hussey/Leonard Whiting Interview (1967) (17:05)
Another of the interviews conducted by Bernard Braden for the never aired TV series Now and Then, this one with 15 year-old Olivia Hussey and 17 year-old Leonard Whiting shortly after completion of their work on Franco Zeffirelli's Romeo and Juliet. It's an interesting chat that focuses largely on their work on the film and their hopes for their respective acting futures. Hussey really does look young here and has a laugh that knocks holes in the sound levels. Nice to hear Bruce Robinson get a mention, an actor who worked on the film but is better known to fans of outsider cinema as the writer and director of Withnail and I.

Booklet
The accompanying booklet is as good as ever, containing a fine essay on the film by Robert Murphy, a smart examination of its social element by William Fowler, an enjoyable look back at its making by director Gerry O'Hara, a piece on The Spy's Wife by Vic Pratt, a recollection of the making of The Spy's Wife by producer Julian Holloway, a short piece on the Bernard Braden Now and Then interview, biographies of Gerry O'Hara and Olivia Hussey, credits for both films, stills, and details of the transfers.

A personal reaction perhaps, but for my money All the Right Noises, in its gentle and unassuming way, is one of the best age-gap relationship dramas I've ever seen, and one of the jewels in the BFI's Flipside strand to date. The picture quality is a little disappointing, but this is likely due to the condition of the original print, the stock used and the lighting conditions under which the film was shot, and in every other respect this is a fine example of small scale British cinema of the late 60s that really does deserve to be more widely seen. Recommended.