I wasn't aware that this movie existed until I saw a VHS copy on a market stall recently and purchased it. I was pleased I did.
A lot of the action takes place on board a steamer travelling from Dover to Calais. A Dutch financier who has forged stock takes the steamer to avoid being found out, but his secretary's boyfriend discovers his secret and threatens to blackmail him. The financier then panics and throws the man overboard into the sea. His is rescued by a search party at the end.
The movie stars Matheson Lang and Constance Cummings. The only actors I am familiar with are Nigel Bruce before he played Dr Watson in the Sherlock Holmes movies with Basil Rathbone and Edmund Gwen, long before he confronted the giant ants in 1954's Them!
Though not brilliant, this movie is worth a look and I rather enjoyed watching it.