An Army doctor who has recently returned from Afghanistan and uses unorthodox methods to save lives, Callahan's brash style does not always sit well with the bosses, but he is a brilliant surgeon and a fearless advocate for his patients.
Appearances
The Night Shift
Main cast, played by Eoin Macken
- Episode 1x01: Pilot (May 27, 2014)
- Episode 1x02: Second Chances (Jun 3, 2014)
- Episode 1x03: Hog Wild (Jun 10, 2014)
- Episode 1x04: Grace Under Fire (Jun 17, 2014)
- Episode 1x05: Storm Watch (Jun 24, 2014)
- Episode 1x06: Coming Home (Jul 1, 2014)
- Episode 1x07: Blood Brothers (Jul 8, 2014)
- Episode 1x08: Save Me (Jul 15, 2014)
- Episode 2x01: Recovery (Feb 23, 2015)
- Episode 2x02: Back at the Ranch (Mar 2, 2015)
- Episode 2x03: Eyes Look Your Last (Mar 9, 2015)
- Episode 2x04: Shock to the Heart (Mar 16, 2015)
- Episode 2x05: Ghosts (Mar 23, 2015)
- Episode 2x06: Fog of War (Mar 24, 2015)
- Episode 2x07: Need to Know (Mar 30, 2015)
- Episode 2x08: Best Laid Plans (Apr 6, 2015)
- Episode 2x09: Parenthood (Apr 13, 2015)
- Episode 2x10: Aftermath (Apr 20, 2015)
- Episode 2x11: Hold On (Apr 27, 2015)
- Episode 2x12: Moving On (May 4, 2015)
- Episode 2x13: Sunrise, Sunset (May 11, 2015)
- Episode 2x14: Darkest Before Dawn (May 18, 2015)
- Episode 3x01: The Times They are A-Changin' (Jun 1, 2016)
- Episode 3x02: The Thing with Feathers (Jun 8, 2016)
- Episode 3x03: The Way Back (Jun 15, 2016)
- Episode 3x04: Three-Two-One (Jun 22, 2016)
- Episode 3x05: Get Busy Livin' (Jun 29, 2016)
- Episode 3x06: Hot in the City (Jun 29, 2016)
- Episode 3x07: By Dawn's Early Light (Jul 6, 2016)
- Episode 3x08: All In (Jul 13, 2016)
- Episode 3x09: Unexpected (Jul 27, 2016)
- Episode 3x10: Between a Rock and a Hard Place (Aug 3, 2016)
- Episode 3x11: Trust Issues (Aug 3, 2016)
- Episode 3x12: Emergent (Aug 24, 2016)
- Episode 3x13: Burned (Aug 31, 2016)
- Episode 4x01: Recoil (Jun 22, 2017)
- Episode 4x02: Off the Rails (Jun 29, 2017)
- Episode 4x03: Do No Harm (Jul 6, 2017)
- Episode 4x04: Control (Jul 13, 2017)
- Episode 4x05: Turbulence (Jul 20, 2017)
- Episode 4x06: Family Matters (Jul 27, 2017)
- Episode 4x07: Keep the Faith (Aug 10, 2017)
- Episode 4x08: R3B0ot (Aug 17, 2017)
- Episode 4x09: Land of the Free (Aug 24, 2017)
- Episode 4x10: Resurgence (Aug 31, 2017)