The Ace of Knaves aka The Saint in Action

This was first published 1937 as The Ace of Knaves by H&S (UK - dated ‘June 1937’) and Crime Club. In 1947 Avon brought out a paperback titled The Saint in Action, but this has not been adopted by others. They also brought out The Saint and the Ace of Knaves a few years later which omits The Spanish War.

Contents: The Spanish War (first published in The Thriller Feb 13 1937 as The Return of the Saint). A tale of violence and forgery. The Saint helps Teal investigate a murder;
The Unlicenced Victuallers (written for this book) which starts with The Saint hijacking a lorryload of booze; and
The Beauty Specialist (first published in The Thriller March 27 1937 as The Z-Man). A blackmailer threatens women with disfigurement.