Debra Morgan (Jennifer Carpenter) is the emotionally charged, foul-mouthed, tomboy sister of the main protagonist Dexter Morgan (Michael C. Hall) on the television show "Dexter." While Dexter usually remains aloof and sometimes very cold towards his sister, Deb never hesitates to say what's bothering her or what's on her mind. Because of Dexter's fascination with death, his adoptive father Harry Morgan (James Remar) took a special interest in him so Deb and Harry never formed a strong relationship. Deb gets transferred to homicide after a couple of years on patrol by Captain Tom Matthews (Geoff Pierson), a close friend of her deceased father. Ever since, she has been working close with the forensics departments and her adoptive brother.
Deb displays her tough attitude through her speech and actions. She is constantly in and out of relationships and breaking down emotionally at the drop of a hat. In Season 1, she finds out that she has been seeing a notorious serial killer dubbed The Ice Truck Killer. After being rescued from almost being killed, she goes through a tough psychological period where she cannot trust men. In Season 2, she meets FBI Agent Frank Lundy (Keith Carradine) and begins an intimate relationship with him. After Lundy leaves, Deb falls in and out of love with other men. She eventually gains the Detective's Shield that she has been after for so long and gains more respect among her unit.
Deb provides the opposition to Dexter's detachment from society with her expressive and blunt personality. Because she has known Dexter his entire life and suspects nothing about his need to kill, she is one of the most important factors in concealing his true identity.
"Say one more thing about my brother and I will kick your nuts down your f***ing throat."
"So, Miami is the haystack and the ice truck's the needle, right? Brother, I just found the f***ing needle!"
"F***ing Beef bus!"