A critical article about the film:
Spy must bring to London a notebook from a secret Turkish-German chemical laboratory. In this laboratory, a terrible German scientist, as a terrible German scientist can be trusted, in a “half-square” on a perverted face (which would look less perverted if not a ugly half-mask), prepares a terrible German poisoning gas.
“A terrible German gas,” it is the iprite “based on hydrogen, not sulfur”!
Oh, at that moment I felt how good it was to be a humanitarian! But I’m sorry to read the article about Iprit on Wikipedia."