He was a Fashion and S&M photographer who was suspected of murder.
Farrow was arrested on suspicion of rape in New York in 2002. The charges were ultimately dropped (according to the lead investigator of the case, the victim was most likely paid off).
His pictures were typically graphic, bordering on grotesque. Among the ones seen was a woman eating her own intestines like noodles using chopsticks. They sometimes featured women who had really been abused by him.
Farrow first appears on Dexter's radar when the severed arm of one of his models, Estrella Carazo, was found inside an alligator by Joe Nix. When he is questioned at the station, Farrow admits to taking photos of Estrella in his studio for a Jamaican rum campaign. He says the photo shoot took place last Thursday, 9:00 until noon. He then tells Debra he could make a her a star but needs to get her in his studio, whip her clothes off, and rough her up a little bit. When Dexter hears this, he decides to make Farrow a higher priority than Arthur "Trinity" Mitchell.
Dexter breaks into Farrow's studio and finds evidence (blood and a fingernail) that Carazo was beaten there. Dexter decides to snatch Farrow from a nightclub, but has to change his plan when Joey Quinn shows up, having followed him there. Dexter sends a woman to distract Quinn and he quickly slips away. Quinn is very annoyed that a "lab geek" ditched him.
During a camping trip, Dexter secretly leaves during the night and abducts Farrow from his home by garroting him until he is unconscious. He takes him into his studio, which is in the same building.
Farrow insists that he didn't kill anyone and he had only beat the women he photographed to create an artistic contrast between beauty and the ugliness in the world. Despite this, Dexter chops off his head with a meat cleaver, dismembers him, and dumps his remains into the Gulf Stream. He then returns to the camping site, not realizing that one of the boys had noticed his absence.
The next day at work, Dexter learns that Angel Batista arrested Farrow's assistant, Timothy Brand, for the murder of Carazo on air-tight evidence -- surveillance photos and DNA. In spite of Farrow's despicable personality, Dexter is left shaken because Farrow didn't meet The Code.
Dexter breaks Farrow's blood slide, and later tells Arthur Mitchell that he killed a man in a "hunting accident."
- If we look closer at Farrow's case it is still a question whether he was aware of Brand's killing spree or not. It is possible that he participated in rape/abuse like Alex Tilden (who also was an accomplice to murder and rapist).
- He is the second character to be killed out of the Code while being a pedophile and a photographer, the first one being Nathan Marten. Both of them are also similar to a character from the novel Dearly Devoted Dexter, Steve Reiker (also a photographer and a rapist) but Farrow seems to be more directly based on Reiker.
- Apart of Reiker, Farrow is also similar to Novel character Alex Doncevic: both of them were alleged murderers who turned out to be innocent, though their personality and art were very disturbing and psychotic. Both also had their lawyers get them free of charges and both were framed by their associates. It should be noted that despite Farrow seeming to be at least partially based on Doncevic, the gap between novel and filming of Season Four is too small to say for sure.