What is the name of Hercule Poirot's secretary?

Hercule Poirot’s secretary is Miss Lemon, whose full name is Miss Felicity Lemon.

Miss Lemon is portrayed as exceptionally efficient, organized, and nearly error-free. Poirot values her administrative abilities and her remarkable knowledge of practical subjects. He famously regards anything she considers worth investigating as likely to deserve attention, reflecting the trust between the detective and his secretary.

She first appears as Poirot’s secretary in the 1935 short story “How Does Your Garden Grow?” She later features in stories and adaptations connected with Poirot’s cases. In Hickory Dickory Dock, a typing mistake becomes important, while another story involves concern about her sister, who works at a student hostel. These details give her a life beyond simply managing Poirot’s correspondence.

A common confusion is with Ariadne Oliver, the mystery novelist who sometimes assists Poirot, or Miss Marple, Christie’s other major detective. Miss Lemon is neither detective nor novelist: her role is Poirot’s highly capable secretary. In the television series Agatha Christie’s Poirot, she was played by Pauline Moran.