Peter is interviewing a coin dealer and is showing Peter a valuable collection when someone breaks in and knocks Peter out.
When he comes to, the police ask for the pictures he took. When Peter develops the film, he discovers a picture he didn't take which appears to be of the robber and it appears to be a woman. Peter chooses not to give it.
Peter talks to the dealer ex wife who could resemble the woman in the picture. It turns out the dealer was behind it and is trying to frame his ex wife. The police think Peter didn't give them all the pictures so he is arrested.