There actually was a sitcom that began with X, called Xerxes, which was a Swedish language show that aired on UK television.
But today behind the little door is the Tim Brooke Taylor sitcom You Must Be The Husband.
Written by Colin Bostock-Smith, it ran for two series on BBC One in 1987 and 1988.
And finally, let’s unwrap the last chocolate in the calendar (I don’t believe in opening a 25th door). In it we find You’re Only Young Twice.
Written by Pam Valentine and Michael Ashton, it starred Peggy Mount and Pat Coombs, and ran for four series on ITV in the 70s and 80s.
Before you go, why not have a listen to the latest episode of setisoppO, the podcast where we work out the opposite of things that don’t have a natural opposite.