Mark Compass began as a frogman for the U.S. Navy and later commanded a few of the ships he had first served upon. He became well known as a capable and courageous captain, as well as a noted nautical investigator. Following his naval stint, Captain Compass was employed as a roving troubleshooter for Penny Steamship Lines. In his capacity as ship's detective aboard the S.S. Nautilus, Compass solved many mysteries on the high seas, as well as preventing crimes on the Nautilus and other vessels in the Penny Steamship Lines fleet. Compass currently lives in semi-retirement in his own personal cabin suite on the Nautilus while sleuthing the occasional seaborne mystery.
- Hand-to-Hand Combat (Basic)
- Diving and Swimming: former frogman.
- Throwing:He knows how to throw bolas, a skill taught to him by a gaucho from the Pampas.
S.S. Nautilus (a liner)
- Although this character was originally introduced during DC's Earth-One era of publication, their existence following the events of the 1985–86 limited series Crisis on Infinite Earths remains intact. However, some elements of the character's Pre-Crisis history may have been altered or removed for Post-Crisis New Earth continuity, and should be considered apocryphal.
- While Captain Compass hasn't appeared in a post-Crisis story, he was mentioned in DC Universe Legacies #3.
- 77 Appearances of Mark Compass (New Earth)
- 1 Images featuring Mark Compass (New Earth)
- Quotations by or about Mark Compass (New Earth)
- Character Gallery: Mark Compass (New Earth)