For the past few weeks Radio 4 has been running a series of late Monday night one-off comedy shows in pursuit of a series. "Patchy" would be the best way to describe them - until this week, when The Secret World came along to show that not only can an old dog learn new tricks, some of them are better.

It reunites the Dead Ringers pair of Bill Dare (producer, writer) and Jon Culshaw, man of a thousand voices, some of which were getting a bit tired. Now Culshaw and a team of impressionists sure to become more famous than they are at the moment have come up with some new ones. Cunningly, some of them are of people whose real voices are unfamiliar.

Mike Leigh is famous, but not for his voice, so we have to take it on trust that it's him running a thriving business providing Method actors as cheap labour while they research parts. And as for Ehud Olmert and Mahmoud Ahmadinejad waking up in bed together after a crazy UN party, all we got was generic Middle Eastern accents.

This meant that the writers had to come up with things that were funny in their own right and, let's face it, the leaders of Israel and Iran in a gay love tryst was not that much of a thigh-slapper. But Peaches Geldof being shocked to discover that her father was involved in that gathering of "dad bands", Live Aid, was. As was Jools Holland trying to escape from a Misery-style stalker. And Amy Winehouse auditioning for the role of Maria in The Sound of Music.