The script held in the Crawford Collection in the AFI Research Collection contains the following character notes (excluding regular characters):
'MICHAEL WILLIAMS. 45, the first murderer. A teacher, he is a clever, dried-up academic, a keen chess player, interested in target shooting. He is involved in an affair with Claudia Jones, a young student teacher, with whom he is deeply in love. Through her, he sees the chance to gain the happiness which his marriage has denied him and he turns to murder as the only practical way to solve the problem of his wife. To protect himself, he is later forced to murder again.
'HELEN WILLIAMS. 39, the first victim, is Michael's wife. She is afaded [sic] homebody, whose whole life revolves around the house and the antique silver she collects. Her marriage has probably turned her into what she is .. a rather pathetic drab.
'EDDIE JACKSON. 50, has a long record for crimes of various kinds. His intelligence is extremely limited .. his straightened circumstances and environment probably made his life in crime inevitable, but he is clumsy and unsuccessful even in that. He is big, shambling, with a violent temper. He is characterised by his great love for his wife, Rose.
'ROGER GREEN. 25, is a young criminal who began his career in Juvenile Courts. He becomes the second victim after he is used by Williams in the set-up to murder his wife and starts to blackmail him. There is very little Green wouldn't do for money. He's essentially a loner.
'CLAUDIA JONES. 24, a kinky spirited young teacher is involved with Williams. She considers herself a "free spirit", and thus takes neither her affair with Williams, nor the ramifications of it too seriously. In fact, she is really experimenting with life trying to find out what she ultimately wants.
'DAISY ROBERTS. 50-ish, is an ex-prostitute now running a boarding house where Green has a room. She is a little flamboyant, a gossip ..... Her long relationship with the police makes her only too anxious to be helpful. Some of her physical attraction has remained with her.
'GEORGE BRENT. 40-50, an ex-crim, is Eddie's cousin. He now runs a Disposal Store. He is neither intelligent nor particularly clean. He helps Eddie, until he departs with his takings.
'JOY. Mac's girlfriend.
'MARY RICE. About 26, is a teacher at Williams' school. Mac learns of Williams' mistress through her. She is rather conservative, not particularly attractive, sympathetic.
'JAMIE REDFORD. 20, is a university student, who, living next to the Williams [sic], is able to help the police in their inquiries. He is slightly impertinent, flamboyantly but not EFFEMINATELY dressed, with good powers of observation. A good kid on the whole.
'THE WARDER. 30-40, in whose care Eddie is released to attend his wife's funeral. He is basically a simple man, but a kind one.
'DOCTOR BROWN. Is called by Williams to examine his wife.
'THE PARSON. Officiates at the funeral of Eddie's wife.
'TWO MOURNERS. At the funeral, a man and a wife.
'CONSTABLE. Who finds the Falcon used in Green's killing.
'DICK TAYLOR. 30-40. A newspaper reporter, arrives at the scene of Green's killing, helps the police.
'AMBULANCE MEN.
'EXTRAS AS BYSTANDERS. At Mac's place when Joy has been injured. (As many as can be afforded).'