Death Knocks Twice (1969) is a Drama, Thriller film that follows when private detective Bob Martin looking for a stolen diamond necklace, he also has a clever serial killer on the trail ... Currently, you can watch Death Knocks Twice on Amazon Video. Streaming availability may vary by country and platform over time. It has a user rating of 4.2 out of 10 from 11 votes. Fans of drama movies may also want to explore similar titles below.