Jane Wilkinson, a famous actress whose married name is Lady Edgware, was in a hurry to trade in her moderately rich husband for an even richer model, so when Lord Edgware is killed, there is an obvious suspect. However, Edgware had just agreed to a divorce - with Poirot acting on his wife's behalf.
Under suspicion, Jane seeks Poirot's help again, having previously wanted his help in ridding her of the same unwanted husband.
So was Lady Edgware the killer, or has she been framed? Her husband also had an unhappy daughter and a nephew who badly needed money.
Poirot soon finds that nothing is at all as it seems in the remarkable world where the theatre collides with high society.