The Murders of Mrs Austin and Mrs Beale

Which is the odd one out:

An ex-call girl wife of a wealthy crook, who has kept one step ahead of the law, a struggling artist married to Stansfield's prospective Conservative party candidate, or the telephone line which links them?

Answer: the telephone line. It isn't dead.

A double murder investigation brings Chief Inspector Lloyd and the newly promoted Inspector Judy Hill together again as colleagues. But the case is a severe test of both Judy's professionalism and Lloyd's ego, and soon threatens their more private relationship . . .