London Assurance **** TNT

Simon Russell Beale and Fiona Shaw have a whale of a time - and ensure that the audience does too - in Nicholas Hytner’s sprightly revival of Irish playwright Dion Boucicault‘s 1841 comedy of town and country manners.

Beale plays Belgravia-based Sir Harcourt Courtly, a plump, preening pigeon of a man, verging on pensionable, whose plan to marry the 18 year old daughter of a Gloucestershire squire is sidetracked by the arrival of Shaw’s hearty, horsy, thigh-slapping Lady Gay Spanker.

It’s a rare treat to see two of the UK’s finest actors on stage together and there’s excellent support from veteran Richard Briers as her doddery old spouse, Nick Sampson giving a supremely supercilious performance as aptly named valet Cool, and a cat-size rat putting in a couple of perfectly timed appearances.

Olivier at the National Theatre, SE1 9PX (020 7452 3000) currently in rep till 2nd June (£10 - £44)