A tough, headstrong NYPD detective in the Major Case Squad, assigned to the 54th Precinct. The eldest son of Francis and Mary Reagan, and older brother to Erin, Joe, and Jamie, he balances family legacy with his relentless pursuit of justice. A decorated Marine veteran, he’s fearless in the field, often relying on instinct and grit over protocol. Known for his fiery temper and stubbornness, he is also deeply loyal, and protective, especially toward his family. He's married to an ER nurse, Linda.