"He had the life expectancy of a match."
In wartime England, circa 1941, poorly-armed tugs are sent into "U-Boat Alley" to rescue damaged Allied ships. An American named David Ross arrives to captain one of these tugs. He's given a key by a fellow tugboat-man -- a key to an apartment and its pretty female resident. Should something happen to the friend, Ross can use the key.
Capt. David Ross

Stella

Capt. Chris Ford

Cmdr. Wadlow

Van Dam

Kane

Hotel Clerk

Weaver

Housekeeper

Baker

Sparks

Grogan
Clerk

American Captain

English Captain

Policeman (uncredited)

Signalman (uncredited)
Seaman (uncredited)

Seaman on W88 (uncredited)
Canteen Hostess (uncredited)

Woman Dancing at Forces Centre (uncredited)
Seaman on W88 (uncredited)
Canteen Worker (uncredited)

Officer in Operations Room (uncredited)
Officer in Operations Room (uncredited)
Dubbing (voice) (uncredited)

Salvage Unit Captain (uncredited)
Soldier at Dance (uncredited)