1920:

The Mysterious Affair at Styles 1920

 

1922:

The Secret Adversary 1922

 

1923:

The Murder on the Links 1923

 

1924:

The Man in the Brown Suit 1924

 

1925:

Poirot Investigates 1925*

The Secret of Chimneys 1925

 

1926:

The Murder of Roger Ackroyd 1926

 

1927:

The Big Four 1927

 

1928:

The Mystery of the Blue Train 1928

 

1929:

The Seven Dials Mystery 1929

Partners in Crime 1929*

 

* = Novellsamling.