Nick Curtis

And oh dear, the characterisations. Emmeline advocated violent protest to win wealthy, older, married women the vote: Sylvia wanted universal suffrage for men and women, by peaceful means. Here, their ideological differences have the air of a domestic spat. Knight and Rose (and Ellena Vincent as Christabel) transcend the stilted relationships through sheer charisma and vocal power.

Director Sam Mendes’s enthralling production blends domestic and world events, a ritualistic family saga, and homages to American culture. There’s a curved Cinerama-style screen at the back of the stage showing the Atlantic, empty Alabama vistas and the changing New York skyline, plus a live, silent-movie style piano accompaniment throughout. The witty performances have more than a touch of vaudeville: I was occasionally reminded of the Marx Brothers.

The script is expertly crafted and sometimes incisive. Steiner doesn’t beat any particular drum, but the central concept strikes chords in contemporary politics, both in recent attempts to limit the right to protest or to strike here, and in more authoritarian regimes overseas.

If you surrender to the absurdity, it's ...

Overall, this is a handsomely mounted, well-acted work that strums reliably on the emotions, but feels inescapably like a museum piece. Scratchy film at the end tells us about the real Jewish-American-German couple that inspired Watch on the Rhine, and Hellman’s own later steadfastness during the McCarthy witchhunts in the 1950s. A new play about either might feel more stimulating.