Madeleine de Sara is an employee of Parker Pyne. She is a disguise artist who customarily plays the role of femme fatale in Pyne's little psychodramas.
In real life she is a quiet, conventional girl (named Maggie Sayers) who lives with her parents in Streatham, South London.
- The Case of the City Clerk (1932)
- The Case of the Discontented Husband (1932)
- The Case of the Discontented Soldier (1932)
- The Case of the Distressed Lady (1932) - employed as an exhibition dancer with Claude Luttrell. During a blackout engineered by her, Claude was to switch a diamond ring worn by Lady Naomi Dortheimer with another.
- The Case of the Rich Woman (1932)
- Problem at Pollensa Bay (1935)
Aliases used by Madeline de Sara
- Dolores Ramona - Problem at Pollensa Bay
- Juanita - The Case of the Distressed Lady
- Grand Duchess Olga - The Case of the City Clerk