GM's Grandson heard from as well

Gm's Grandson was also a writer, primarily of mysteries.  This is a copy of Warrant for X

1938 Doubleday edition.  Many of his books were made into films, 

From

British novelist Philip MacDonald was born in London, England, in 1901. His grandfather was the Scottish novelist George MacDonald. As a young man Philip was an excellent horseman; prior to World War I he trained horses bought from Argentina for the British army, and when war broke out he enlisted in the army and was posted to a cavalry unit in Mesopotamia (modern-day Iraq).

He began writing while in the army, and his first detective novel--the genre for which he is best known--was "The Rasp", published in 1924, which introduced his main character, a detective named Col. Anthony Gethryn. This was followed by a dozen more novels featuring Gethryn. MacDonald didn't confine himself solely to crime thrillers, however. His novel "The Patrol" (1927) was about a squad of British soldiers on patrol in the Mesopotamian desert during World War I and have to survive constant attacks and ambushes by rampaging Arab bands. It was filmed, quite successfully, by directorJohn Ford as The Lost Patrol (1934) in 1934.

MacDonald also wrote original screenplays, his most famous probably being that forAlfred Hitchcock's Rebecca (1940), and also turned to writing for television, penning episodes of series as diverse as Wagon Train (1957), Alfred Hitchcock Presents (1955),The Virginian (1962) and Robert Montgomery Presents (1950).

Philip MacDonald died in Woodland Hills, CA, in 1980.

IMBD  "

I loved The List of Adrian Messenger and recommend that one for any old movie buffs