Dr David Mortimore is about to deliver an important speech at a neurologist's convention which will probably earn him a knighthood. Unfortunately for him, an old flame turns up with his love child, Leslie, who is now 18 and desperate to meet his father.

Frantic to hide the devastating news from his wife and the hospital authorities, David enlists the help of his colleague Dr Hubert Bonney in a complicated web of subterfuge, lies and trauma. 

Into the mix comes young Dr Connelly who is trying to sort out the annual Christmas pantomime complete with costumes, a police sergeant on the trail of he knows not what, a wandering senile patient unsure of who or where he is, and a matron who tries to hold things together, even when she is perched on a window ledge three floors up and at the wrong end of a syringe full of tranquilizer!