You can tell how corrupt our recent politicians have been by how attractive Harriet Walter’s portrayal of the ex-PM seems alongside Steve Coogan in this drama based on a scorching TV interview

Brian and Maggie is a two-parter billed as a docuseries by its creators that traces the relationship between former Labour MP turned journalist Brian Walden (Steve Coogan) and Conservative prime minister Margaret Thatcher (Harriet Walter) and its abrupt ending, brought about by his uncustomarily scorching interview with her after chancellor Nigel Lawson’s shock resignation in 1989.

Written by Sherwood’s James Graham, it is directed by Stephen Frears and boasts a cast full of notables fit to stand alongside Coogan and Walter. Yet it is an odd beast, perhaps because it is trying to do so much. It is partly an examination of the importance of the long-form political interview, for which Walden was famous, in a democratic society, and a lament for a bygone age when the argument for it could still be made. It is partly an examination of proximity to power and the cosiness that can develop between people who move in overlapping circles, the boundaries that can be crossed and what happens if you try to re-establish them. It’s about friendship, commonalities, betrayals of many kinds. It’s about 80s politics generally, Thatcherism specifically, the attraction felt for an ideologue and the ramifications when it wanes. It’s about class politics too, as Walden and Thatcher bond over their own-bootstraps upbringings and earned entry into the rarefied worlds of media and politics that their publicly schooled colleagues were effortlessly ushered into.

Brian and Maggie is on Channel 4 now.