Marshall Pugh is a British journalist and author. He wrote a book called Commander Crabb based on the true story of a British officer who learned deep sea diving to thwart Italian frogmen who were sabotaging British naval forces. He later adapted it into a movie called The Silent Enemy

The Silent Enemy (film)

The Silent Enemy is a 1958 action film directed by William Fairchild. It stars Laurence Harvey as Lionel "Buster" Crabb and describes his exploits during World War II...

which was released in 1958.
He also wrote fiction, including the novel "A Wilderness of Monkeys" which was published in 1958. A list of his work is available at http://openlibrary.org/a/OL1947915A/Marshall-Pugh