A double bill of Alan Bennett’s witty writing is tempting fare and this rendition of An Englishman Abroad and A Question Of Attribution does not disappoint.

The first play covers a real-life meeting in Moscow between exiled spy, Guy Burgess, and the actress Coral Browne.

Nicholas Farrell portrays the homesick, down-at-heel spy with shambolic style against an imposing backdrop of Stalinist architecture but the overall effect is a little “so what?”

For it is truly the second play which makes the evening and sheds light on the first.

David Robb (Downton Abbey’s Dr Clarkson) is a marvellous Sir Anthony Blunt - surveyor of the Queen’s pictures, lecturer at the Courtauld Institute and a known spy under investigation by MI5.

As the action slickly moves between interrogation (Farrell now playing an affable art-loving MI5 officer), lectures on art attribution and an amusing exchange between Blunt and the Queen, serious ideas of fakery, hidden identities and motivation emerge.

Echoes of the first play help contrast Burgess’s sorry state with the privilege Blunt still enjoys - for the present.

It’s an intense night’s work of double duty for the three main actors but they pull it off and do justice to Bennett’s clever dialogue.

Four stars