BRUNO (ignoring the remark) It's so simple, too. A couple of fellows meet accidentally, like you and me. No connection between them at all. Never saw each other before. Each of them has somebody he'd like to get rid of, but he can't murder the person he wants to get rid of. He'll get caught. So they swap murders.
GUY Swap murders?
BRUNO Each fellow does the other fellow's murder. Then there is nothing to connect them. The one who had the motive isn't there. Each fellow murders a total stranger. Like you do my murder and I do yours.
GUY (with relief) We're coming into my station.
BRUNO For example, your wife, my father. Criss-cross.