Edwin Arnold (Hywel Bennett) is an antiques dealer who is delivering a chandelier to a woman who had visited his shop earlier. Unbeknownst to him, in one of the flats above him, a man and a woman (Elke Sommer) are carrying on an affair, which is rudely interrupted by the woman's husband arriving home early and hammering on the door to be let in. Panicking, the man leaps out of bed and heads for the balcony to hide - unfortunately, he's got his mistresses mixed up and there is no balcony in this flat. He falls to his death, landing on Edwin and causing a rather nasty accident, one which greatly interests pioneering transplant surgeon Emmanuel Whitbread (Denholm Elliott). Making medical history, Whitbread will take the dead man's penis and replace Edwin's severed one with it.
At first glance, Percy may look like any other British sex comedy of the seventies, with plenty of snickering about the hero's predicament. Whitbread appears on television and finds that every time he says "penis", the director bleeps him out, causing him no end of anger. But he's not above making smutty jokes himself: "Penis from Heaven", "See how it stands up in the light of day", that sort of thing. However, as the film progresses, it becomes more of a drama, as if the idea of penis transplants should be taken very seriously indeed due to the psychological effect it will have on the recipient. Written by Terence Feely from a novel by Raymond Hitchcock, it's undoubtedly a novelty piece, but can't seem to decide whether it should be stuffed with jokes or be more contemplative about its subject.
Edwin isn't having much luck. Not only was he separated from his manhood in a chandelier accident, but his wife, Hazel (Janet Key), is running off with his best friend James (Patrick Mower). They only know he's in hospital (but go on holiday anyway - that's cold), as the operation has been kept a secret - but how long will that last? Whitbread and his staff test out the efficiency of Percy, as the penis is now called, by calling on a stripper dressed as a nurse to see what effect it has on Edwin and his new friend, and the result can only be judged a success. But Whitbread can't keep it to himself, and alerts the newspapers about his achievement, leading everyone to wonder who the transplant patient was. Edwin is discharged, but turns down the offer of a private sanctuary to hide out in to carry on with his old life.
However, the identity of the donor is preying on Edwin's mind, and he manages to get a list of the possible men who gave up their lives for his sexual wellbeing. From then on Percy is a repetitive experience as he visits the wives of the might-be donors to see if they can identify the penis, something which is easier said than done. It sounds like a porno, doesn't it? He tries to get almost all of them into bed (he's also keen to see if the thing works properly), but is continually frustrated, either by lack of condoms or his sense of morality. Then he finds Moira (Cyd Hayman), the wife of Guy, who is indeed the previous owner of Percy, and who was in life a serial philanderer, leaving Moira deeply cynical. Edwin then moves onto interviewing Guy's mistresses, including guest stars Sommer and Britt Ekland, feeling he should be carrying on Guy's work.
As a comedy, Percy has a few good jokes (such as what happens when a trouserless Edwin escapes through the window of an adjacent flat), but its protagonist is too dour and self-pitying for the film to really take off and fly. Elliott seizes every chance he can, but Bennett tends to mope, despite a dream sequence which has him imagining he is George Best scoring goals, or a racing driver, or Mick Jagger at Hyde Park with the Rolling Stones. What the film is best remembered for today, if at all, is the music by the Kinks on the soundtrack (an instrumental of "Lola" over the stripper scene is the most recognisable bit), all of which is about as cheerful as Edwin. By looking at penis transplants from the angle of medical breakthroughs and the source of public amusement simultaneously, Percy is not your average sex comedy, and is unusual enough to be worth a look, even if Edwin doesn't get much of a chance to try the other hero out. Listen for: the strange version of the News at Ten theme.