This is a pleasing but imperfect dramatisation of Simon Gray’s late memoirs, in which the author’s mordant wit and rigorous self-examination strained to embrace the terminal cancer caused by his 60-year, 60-a-day cigarette habit. Gray was working on the adaptation before a fatal aneurism overtook the cancer in 2008. Funny: Gray’s later books sprang from frustration with his stagnating stage career; now he’s back in the West End thanks to the diaries.

Richard Eyre’s production casts three actors as Gray. The first half is about family and friends and loss, the second about his fear of death or, worse, nicotine deprivation. It’s smart, very funny and at times harrowing, pitiless about the pitiful addictions to which Gray and many in his family were prey.

The triple-casting suits the writer’s lolloping, associative prose and his tendency to interrogate his memories and motives. It also feels like a cheeky way of dramatising something that worked better on the page. Loosely speaking, Jasper Britton plays the man to whom the diagnoses happen. Nicholas Le Prevost is the authorial voice. Most bizarrely, a breathless Felicity Kendal plays the women in Gray’s life and also his feminine side, when he sentimentally recalls family members or a gay schoolboy crush. All three wear denim shirts and smoke fake fags, rhythmically but uncomfortably.

If the staging coarsens and dissipates some of the first-person pungency of Gray’s books, it also boosts some of his jokes. “I screamed only once,” he says of a humiliating catheter-removal, “but at length.” The actors also manage to evoke his wife Victoria and friend Harold Pinter without describing them. The memoirs seemed brave and craven, wise and stupid. This stage adaptation is arguably funnier but somehow also sadder.
Booking to 1 August (0870 060 6632, www.ambassadortickets.com)