Conversation so far:
what is the film noir?
Mitchum was initially known for his work in film noir.
what was his role?
His first foray into the genre was a supporting role in the 1944 B-movie When Strangers Marry.
how did that movie do?
CANNOTANSWER.

Question: who acted alongside with him?
Self-contained rewrite: Who acted alongside Robert Mitchum in When Strangers Marry?