Mabel West, holidaying with her father in Brighton, meets Poirot and Hastings and becomes involved in a case.

Mabel West leaves boarding school to go to London where she offers to work for Poirot. At first Poirot refuses but then Mabel stumbles on a puzzle which interests him.

Mabel West is visiting her great aunt Miss Marple. A young couple arrives to seek Miss Marple's help in finding some buried treasure which they believe their late Uncle Matthew bequeathed to them.

Mabel West visits her great aunt Miss Marple. At St. Mary Mead, Mabel meets Gladys, a friend of hers who has just been dismissed from her job. Mabel persuades Miss Marple to help.

Lord Estair, the Home Secretary asks Poirot to help find the prime minister who has been kidnapped. However he is not used to Poirot's methods.

Sir John Willard, a noted archaeologist dies while excavating an Egyptian tomb. Lady Willard is worried because her son, Sir Guy Willard intends to carry on his father's work, regardless of the risks. She confides in Poirot that she is worried about the talk on the ground that a curse is at work at the site. Poirot agrees to protect her son.

Mabel West gets involved in another murder investigation while visiting her great aunt Miss Marple at St. Mary Mead. A woman is found dead but her husband does not seem to be very upset. Naturally the suspicion falls on him.

While watching Mabel participate in a treasure hunt, Miss Marple tells her about a mystery her father was involved in many years ago.

Miss Marple and Mabel West are asked to help solve the mystery of the death of Mrs Mary Pritchard.

Poirot, Hastings and Mabel are at St. Loo enjoying a hotel that was a reward for solving a burglary. There they meet Nick Buckley who says she has had several narrow escapes in the past few days.

Poirot is asked to help recover a ruby for a foreign prince.

Elspeth McGillicuddy, a friend of Miss Marple, witnesses a murder on a passing train while on her way to visit St Mary Mead. The police stop investigating when they cannot find the body. Mabel persuades Miss Marple to send her on a dangerous undercover mission to find out the truth.

Poirot, Hastings and Mabel investigate the murder of a woman whose body was found on the Plymouth Express.

A visiting lawyer, Mr Petherick, tells Miss Marple an Mabel West about a strange case where a will was changed but those who had the opportunity to do so did not have the motive while those who had a motive did not have the opportunity.

Poirot, Hastings and Mabel are asked to find a cook who has disappeared.

Poirot becomes interested in a regular diner at a restaurant turns up on a day he does not habitually come and who then orders something he does not habitually eat.

The well known banker Mr Davenheim has disappeared. Sharpe challenges Poirot to solve the mystery within one week without leaving his apartment.