The Long Arm

Supt Tom Halliday

Sergeant Ward

Mary Halliday

Tony Halliday

Police Constable in Information Room

Detective Sergeant in 'Q' car

Nightwatchman / Gilson

Deputy Commander

Chief Superintendent Jim Malcolm

Stone

Creasey

Slob

Detective Inspector at Chester

Colonel Blenkinsop

The Young Workman - Stanley James

The Young Workman's Wife - Mrs. James

Detective Inspector at Shipping Office

Cashier at Shipping Office

Detective Constable in Hospital Ward

House Surgeon

Secondhand Dealer

Police Constable Bates

Newspaper Circulation Manager

Mrs. Elliot / Mrs. Gilson

Welsh Police Constable

Welsh Newsagent's Daughter

Mr. Thomas

Official at Somerset House

House Agent at Shepperton

Housewife at Shepperton

Mrs. Stevens, the daily help

Detective Superintendent Ogilvie

Manager of Festival Hall

P.C. at Hospital (uncredited)

Detective (uncredited)

Urchin (uncredited)

Constable (uncredited)

Detective at Car Lot (uncredited)

Detective (uncredited)

Detective tailing Creasey (uncredited)

CID Man (uncredited)

Officer in Criminal Records Department (uncredited)

Detective (uncredited)