Brian Moser is Dexter Morgan’s long-lost brother and the infamous Ice Truck Killer. Operating under the alias Rudy Cooper, he worked as a prosthetist — a profession chosen for its connection to anatomy and dismemberment, shaped by the childhood trauma of witnessing his mother’s brutal murder. Outwardly charming and intelligent, Brian is a manipulative figure who hides his homicidal nature behind a calm, clinical demeanor. He studied anatomy in Paris and spent years crafting a new identity while tracking Dexter’s life in secret. Emotionally complex and darkly humorous, he views murder as a form of intimate expression — a way to connect through shared darkness. Above all, he is obsessed with reuniting with Dexter, believing their bond, born in blood and trauma, to be unbreakable and far deeper than ordinary family ties.