Forty years after her death, Agatha Christie is rivalled as an authorial source of entertainment only by Shakespeare and Dickens. This English Christmas alone, a new adaptation of Murder on the Orient Express is in cinemas, and Ordeal by Innocence would have occupied Boxing Day BBC1 peak-time until its postponement while an actor defends himself against allegations (which he denies) of sexual assault unconnected to the project.

London theatregoers, meanwhile, have a choice between the sixty-fourth year of The Mousetrap and a revival of the next play that Christie wrote: the courtroom drama, Witness for the Prosecution.