This is a super rare movie. This DVD looks brilliant. Scenes look like they were shot yesterday. This is due in part to the film being shot by Lazlo Kovacs. Kovacs photography really stands out on his early black and white films like this film and The Sadist. Mark of the Gun was in a vault for 45 years and it is very hard to find any info on it. It is a very well paced high action movie. The movie has an entertaining plot and the characters are very likeable. Ross Hagen stars with his real life wife Claire Polan. However, Claire Polan is billed in the film credits as Gabrielle St. Claire. There are many other pleasant actresses in the film which I suspect are billed under pseudonyms as well. There are groundbreaking themes in the plot and a scene involving one of the women for the period. The movie is copyrighted 1966 in the credits although imdb.com has it listed as 1969. The DVD includes some bonus material of Ross Hagen's other movie works in his career. Fans of low budget exploitation of the era and Ross Hagen completist can't go wrong with buying this DVD.