Big screen spin off from the BBC TV series The Grove Family, ostensibly the first British soap opera. Bob Grove, a builder has problems with the council, over building supplies that he needs to complete a job on a local housing estate. Under pressure to finish the job, his son gets them from a local crook. When the council find out, they call in the police, so the Grove family get together, to clear themselves, in time for the grand opening.
A trip to the theatre changes a meek bank clerk's life, as he undergoes hypnosis and leaves without being woken up. Suddenly, he believes he is the world's greatest lover and becomes a terrorizing Casanova.