Nestling behind the thirteenth door, we find another Esmonde & Larbey sitcom, and another of their collaborations with Richard Briers.
No, not The Good Life, nor Ever Decreasing Circles, but the 1977 and 1979 BBC show The Other One, which co-starred Michael Gambon. I can’t find too much information about this, but it’s about a liar, hence the title. Both Briers and the writers list this as some of their finest work. It’s slow to start, but has a nice climactic set piece which doesn’t go the way you’d expect: