The Mysterious Key

How did the murderer to close the door and then leave the key inside the room? George Brown, the policeman finds out that there was only one key, the same one found at the scene of the crime. Even more, the same key that the victim always had it hanging on his neck. The story is enlivened by an attractive blonde, Eve Russell, a sensuous beauty who is quite involved in the case, who makes a play for Ken Brown first and then for his brother George.