Free Dutch agents have smuggled diamonds into the US to keep them away from the Nazis... though a Nazi gang is hot on their heels. Ellery Queen (William Gargan) and Nikki Porter (Margaret Lindsay) are dragged into the case, at first thinking the Dutch agent Gillette (Gilbert Roland) is a criminal but soon they discover the truth. The case is a complicated one with some unexpected twists.
This was the final entry in the Ellery Queen series and the series ends on a high. A lot is packed into the war time plot and it ends with some good rough humour in the final fight scene. Of course, there is a bit of a propaganda edge to the film though this doesn't overbear the story.
