✓ Correct! Harry Morgan, Dexter’s adoptive father and a Miami homicide detective, recognized Dexter’s dark urges early and taught him “The Code of Harry” — a set of rules to ensure he only kills other murderers and never gets caught.

✗ Sloppy work! The answer is Harry Morgan. Doakes was suspicious of Dexter, Angel Batista was his colleague, and “James Doakes” is Doakes’ first name but he didn’t teach the Code. Harry is the father who shaped the Dark Passenger.

✓ Correct! Blood spatter analysis — the irony of a serial killer who specializes in blood at crime scenes is central to the show’s dark humor. Dexter uses his expertise to both solve cases and cover his own tracks.

✗ Sloppy work! The answer is blood spatter analysis. It’s the defining irony of the show — Miami’s most prolific serial killer is the department’s blood expert. His knowledge helps him commit perfect murders and clean up without leaving evidence.

✓ Correct! “Surprise, motherf***er!” became one of TV’s most iconic lines, delivered by Erik King as Sergeant James Doakes. His gut feeling about Dexter was right all along, making him one of the show’s most tragically correct characters.

✗ Sloppy work! The answer is “Surprise, motherf***er.” Erik King’s delivery of this line as Doakes became a cultural phenomenon and internet meme. Doakes was the one person who saw through Dexter’s mask from the very beginning.

✓ Correct! Brian Moser is Dexter’s biological brother, separated from him after they both witnessed their mother’s murder as children. Brian became the Ice Truck Killer, leaving carefully staged crime scenes to attract Dexter’s attention and reunite with his brother.

✗ Sloppy work! The answer is Brian Moser — Dexter’s biological brother. Miguel Prado is the Season 3 antagonist, Arthur Mitchell is the Trinity Killer (Season 4), and Jordan Chase is the Season 5 villain. Brian’s reveal as Dexter’s brother was the show’s first major twist.

✓ Correct! Arthur Mitchell, played brilliantly by John Lithgow, maintained a façade as a devoted family man while committing ritualistic killings in cycles of three. The Season 4 finale — where Arthur kills Rita — is considered one of the most shocking moments in television history.

✗ Sloppy work! The answer is Arthur Mitchell. George King (the Skinner) is from Season 3, Oliver Saxon is the Season 8 villain, and Brian Moser is the Season 1 Ice Truck Killer. Lithgow’s portrayal of Arthur Mitchell earned him an Emmy and is regarded as one of TV’s all-time great villain performances.

✓ Correct! Debra rises through the ranks from detective to Lieutenant of Miami Metro Homicide. Her promotion to Lieutenant is a major plot point, and her gradual discovery of Dexter’s true nature becomes one of the show’s most emotionally devastating storylines.

✗ Sloppy work! The answer is Lieutenant. Debra starts as a vice detective, becomes a homicide detective, then rises to Lieutenant. Her professional growth mirrors the show’s escalating tension as she gets closer and closer to uncovering her brother’s secret.

✓ Correct! Dexter goes by “Jim Lindsay” in the fictional town of Iron Lake, New York, where he works at a local fish and game shop. The name “Lindsay” is an easter egg — Jeff Lindsay is the author of the Dexter book series that inspired the show.

✗ Sloppy work! The answer is Jim Lindsay. The alias is a clever nod to Jeff Lindsay, the author who created Dexter in the novel “Darkly Dreaming Dexter.” In Iron Lake, Dexter tries to suppress his Dark Passenger but is inevitably drawn back to killing.

✓ Correct! Plastic sheeting (often referred to as “plastic wrap” or “saran wrap”) is Dexter’s signature kill room material. The imagery of Dexter meticulously covering a room in plastic became one of the show’s most iconic visual motifs, symbolizing his careful, methodical approach to murder.

✗ Sloppy work! The answer is plastic sheeting. The clear plastic wrap covering every surface of the kill room is one of Dexter’s most recognizable visual signatures. It represents both his forensic expertise — no DNA or evidence left behind — and his ritualistic preparation.