Terry Jastrow’s play speculates on what happened when in 1988 Jane Fonda met a group of irate Vietnam veterans threatening to halt shooting of her latest film in Waterbury, Connecticut. While Jastrow has clearly done his homework, I can’t believe the encounter so closely resembled Twelve Angry Men: a movie that, ironically, starred Jane’s celebrated father.

Of the men here assembled to accuse Fonda of treachery in paying a visit to North Vietnam in 1972, only one – the episcopalian pastor who is hosting the meeting – keeps his cool. The others are implacable in their hatred of an actor who they believe transcended anti-war protest by visiting Hanoi: among the more polite insults thrown at her is that of being “a pot-smoking, promiscuous political activist”.

Everything ultimately hinges on the shots of her sitting astride an anti-aircraft gun of the kind used to kill American troops. One of Jastrow’s key points, and Fonda’s, is that the media distort reality. But that argument is subverted by use of film footage showing Fonda constantly laughing during her exposure to Hanoi’s armoury.

The good thing about the play is that it reminds a new generation of the passions aroused by Vietnam: the weakness is that it shows the abusive veterans forced into grudging admission of the war’s futility. Even if Fonda improbably keeps her composure under withering abuse, Anne Archer radiates the right rational calm and Paul Herzberg stands out, in Joe Harmston’s production, as a vehement, finger-stabbing vet. I just find it hard to credit that the actual meeting followed the neat pattern of a liberal Hollywood movie.

• At the Park theatre, London, until 20 August. Box office: 020 7870 6876.