Secret Service is a 1931 American Pre-Code drama film directed by J. Walter Ruben and written by Bernard Schubert.

Two Union officers, Captain Lewis Dumont and his younger brother, Lieutenant Henry Dumont, receive orders from General Ulysses S. Grant Grant to go behind enemy lines and become undercover agents to feed false information to the Confederate States Army.

Meanwhile, Henry is ordered to allow himself to be captured by the enemy, during which he is supposed to pass incorrect information about Union positions.

However, this creates enmity with one of the locals who was interested in Edith prior to Thorne's arrival, Arlesford.

The elder Dumont, torn between duty and his love for Edith, is eventually uncovered as a spy.