Mr. Reeder in Room 13 is a 1938 British crime film directed by Norman Lee and starring Peter Murray-Hill, Sally Gray and Gibb McLaughlin.

Reeder enlists the aid of a younger man, Captain Johnnie Gray, to infiltrate the gang by going undercover in Dartmoor jail.

"[5] Kine Weekly wrote: "The acting is in the main good, and powerful suspense accompanies the climax, but the story is far from easy to follow.

Sally Gray is adequate as the heroine and Gibb McLaughlin is good in the title role, but the rest of the cast is hindered by the story development.

"[7] Britmovie wrote, "Director Norman Lee keeps things moving along briskly and packs plenty of goings-on into its relatively short running time, but the outlandish plot requires some suspension of disbelief.