Straight, Bush Theatre, London

Straight, Bush Theatre

How far would you go to prove that you had not become stuffy and predictable? That's one of the questions posed by Straight, D C Moore's entertaining rewrite of the 2009 US Indie movie, Humpday.

Lewis (Henry Pettigrew) and Morgan (Jessica Ransom) are a young married couple struggling with negative equity but settled and planning to have a baby. Then, after seven years of backpacking round the world, Waldorf (Philip McGinley), Lewis's best buddy from university, crashes into their lives, having first announced himself through the letterbox in a distinctly individualistic manner.

Cue for Lewis to start feeling that it is not just the studio flat that is cramping as the chaotically cool Waldorf borrows the marital bed during working hours to entertain a stoned, ditsy porn actress (Jenny Rainsford) and cocks a sceptical eyebrow at his friend's stable circumstances while taking full advantage of them. 

A drunken dare is made and the second half of Richard Wilson's expertly-acted production sees the male duo in a lavish hotel room with a camcorder working up the courage (amongst other things) to test the boundaries of their relationship for Humpfest, a festival of alternative ,“holistic”, non-commercial porn, seen once communally then ritually burned.

Neither of the men is gay, though they worry about what their tumble may unleash and Lewis, whose mix of twitchy inhibition and hesitantly dawning spirit of adventure is beautifully conveyed in Pettigrew's fine performance, launches into a daft but oddly touching account of an unspoken undergraduate crush on a male assistant in a video-store. 

Rather than insecurity about orientation, what the play deftly captures is that hunger for wild, category-shattering experience that may – or may not and that's the risk – enable one to return to everyday normality with the grateful sense of now having made a real choice. 

The play has its implausible moments and sometimes sacrifices discomfiting subtlety for a broad, and slightly forced, sitcom approach, as when – in a “panic buy”, to minimise embarrassment in the shop – Waldorf arrives for the encounter with more types of lubricant than you could, well, shake a shillelagh at. 

But McGinley's portrayal of the character nicely traces his journey from louche bravado to a kind of anxious delicacy. And Ransom's Morgan, bewildered and stung into revealing one night of infidelity of her own, matures, with finesse, from solid good sport to concerned, stoic realist. 

To 22 Dec; 0208 743 5050