Imagine This, New London Theatre, London

Could it get worse at the New London than Gone with the Wind? It could. And it just did. Imagine This is a Holocaust musical that makes Springtime for Hitler look like The Sound of Music. You can have bad taste and call it laughter in the dark, but it's something else when Peter Polycarpou's ghetto leader Daniel staves off the evil moment with a string of Jewish jokes, such as the one about the boy who tells his mother he's playing a Jewish husband in the school play. He's pleased. She's not. "Tell them you want a speaking part," she fumes.

Laugh? I nearly died, whereas the Warsaw Jews actually did, just like the zealots who fled burnt-out Jerusalem and defied the Romans by committing mass suicide on the rock at Masada. The presentation of the play runs parallel with the violence in the ghetto, some of which is deeply unpleasant.

Before the interval, the Nazi chief interrupts with good news as we make our way to the bars. What could it be? We don't have to come back? The drinks are free? No, it's a promise of bread and jam and a free train ride if we only take one suitcase. As the resistance fighter Adam (who doubles as a Roman waverer) knows all about Treblinka, the outcome, as they say, is never in doubt.

The Masada play takes us to Rome where Bernard Lloyd's Caesar issues the massacre instruction and his general declares that the soldiers must be hailed, or the zealots will be nailed. Hailed or nailed, what's it to be?

One hates to be inhospitable, but the show comes from America with minimal creative provenance. The music has some predictable and over-used harmonic shifts, a catchy rhythmic lilt to the title song, a brow-beating intensity to "Masada", and that's it. Did no-one think to put a klezmer band on stage or research the songs of the ghetto?

I liked Simon Gleeson's febrile, attractive Adam, but Leila Benn Harris's Rebecca is an annoying "West End" performance. The excellent Michael Matus has a comic turn as a sacrificial victim and Polycarpou consolidates his leading man status with dignity, passion and a fine baritonal tenor voice.

Director Timothy Sheader arranges some impressively tough-to-watch sequences, such as the slow-motion suicide pact and the elisions between backstage on the show and full occupation of Eugene Lee's imposing warehouse design of steel girders and broken windows. The show looks good. But do me a favour, spare me the schmaltz.

Booking to 28 February (0844 412 4654; www.imaginethisthemusical.com)