Jingo, Finborough Theatre, London

"I cannot be shackled... I'm frightfully flighty," says Gwendoline, who sounds like a dainty miss of music hall but is in fact, her former and present husbands agree, a slut. This doesn't stop George, her young and silly spouse, and Ian, her grave and sensible ex, from wanting her – the latter even tells George that he is going to get her back.

But Gwen and the two Army officers are in the midst of a more serious conflict. They are in Singapore in early 1942, and George, who scornfully dismisses the idea of being bombed by the Japanese with "I'd like to see them try!", is about to get his wish.

Jingo is one of many plays about men in war, written for stage and TV, in the Sixties and Seventies (in this case, 1975) by Charles Wood, author of the unforgettable Falklands drama Tumbledown. They reflect not only Wood's Army experience but the savage anti-Establishment mood of their time: George, the "expert" on the Japanese, calls them "little yellow monkeys", and is sure they'll be no good in battle because they all need glasses. Another officer, Percy, could be speaking for them all when he asks, "Have you ever been buried alive? I have."

In Tom Littler's production, for the Primavera company, every performance is first rate – Susannah Harker's ice-blond bitch; Peter Sandys-Clarke's absurd but touching George; Anthony Howell's sorrowing Ian, trapped by a crazy passion and a chaotic war. Best of all is Paul Mooney as the lecherous Percy, whose hearty banter veils terror and shame that have turned into sexual masochism: "I am responsible for the end of the British Empire as we know it. Doesn't that make you want to whip me?"

Unfortunately for Wood, his former collaborator Peter Nichols came up, two years later, with Privates on Parade, a much richer and more unusual treatment of this milieu, whose success has probably contributed to the neglect of Jingo (this is its first revival).

But this "farce of war" has problems of its own – the shifts in tone feel awkward rather than disturbing, and the characters, though more than types, are not quite real. Except for Percy, what they say simply reaffirms instead of expands their personalities. Gwendoline doesn't have enough outrageously funny lines to redeem her hatefulness (even the Chinese servant calls her behaviour "awfully bad form"), or George enough to balance his foolishness.

What will happen to Singapore may be known to us from the beginning, but, in showing how individuals meet their fate, the playwright has too few surprises.

To 19 April (0844 847 1652; www.finboroughtheatre.co.uk)