"Lawrence of Arabia there, with me, in the psoriasis chair." Count Arthur Strong is screening clips of his 50-year TV career. There's a Face to Face with Lawrence of Arabia - sorry, Olivier - and Doctor Who with the Count as a grumbling Cyberman. Steve Delaney (the comic behind the cult Radio 4 character) has spliced himself, Zelig-style, into footage from telly's early years to establish that Count Arthur didn't degenerate into incompetence. He's been like that all along.
The clips are among the show's highlights: there's a precious one in which he presents 70s game show Ask the Family. Otherwise, The Man Behind the Smile sees the confused old soak look back in mounting anger at his career.
Delaney's performance is airtight. The wrongness of the malapropisms is word-perfect, as Arthur tacks ever wider from a courtly script and an aristocratic persona. We hear about Longleat, where the Count was banned from sitting in a little teacup, and backstage at Just a Minute, where Nicholas Parsons bagged the best vol-au-vents and "Clement Freud went home with three pounds of hummus in his cupped hands".
If the show isn't as brilliant as the character, it's because we experience the same frustration he does. His senility derails every train of thought before its conclusion, so we're led up dramatic dead ends. What's left is the Count, tilting at windmills - that "bastard Melvyn Hayes on The South Park Show", for example - as his show, and his vainglory, disintegrate around him. It's a painfully precise comic performance. Olivier, I suspect, would love it.
• At Royal Spa Centre, Leamington Spa (01926 334418), tomorrow, then touring