Duane was the boss of Sarah, former girlfriend of Tim Bisley. Tim looks back on his association with Duane as a period of friendship, but Duane is seen abusing and mistreating Tim multiple times. Sarah eventually left Tim for Duane.
Duane, while mentioned before, first appears in the episode "Battles", in which he encounters Tim and Mike Watt at the paintball arena. Duane acts condescendingly towards Tim, making it worse as they are on the same team. However, during the battle, Tim witnesses Duane shooting a teammate. They finally confront each other, but their paintball guns have run out of CO2; however Duane has bought an extra canister. Just as he is about to shoot Tim, Mike rushes out, screaming, and throws two guns to Tim before diving in between them, taking Duane's shot in the chest. Tim shoots Duane directly in the groin, exacting his revenge. He then shares an emotional and dramatic moment with Mike, who has sort of made the ultimate sacrifice. They then leave the paintball arena feeling content and refreshed. Duane is seen being taken away in an ambulance.
In the episode "Ends", it is revealed that Sarah and Duane broke off their relationship. She attempts to get back together with Tim, but he turns her down. She and Duane end up back together.
Duane appears once more in "Gone", in which he steals Tim's house keys in an act of revenge for the paintball incident. However, he ends up in a traffic collision with the Romford thugs who were formerly antagonising Tim and Daisy. He gets out of his car to confront the driver, and the driver stares him down whilst his gang approach from behind. In a homage to Jurassic Park, he mutters "Clever boys", just before the gang beat him up.
- “See Tim, that's the difference between you and I. Organization. Careful thinking. Forward planning. And that is why I sleep in the arms of a beautiful woman and you spend your evenings alone in your bedsit. With cheap porn.”
- — Duane Benzie to Tim Bisley during the paintball standoff in "Battles".
- “At last, I will emerge as the victor. At last, I will have... revenge.”
- — Duane Benzie after stealing Tim's house keys in "Gone".
- “You bloody idiot! Have you any idea how much this car cost? Why don't you piss off back to Romford where you belong. You little prick! Eh? Eh?”
- — Duane Benzie to the leader of the Romford thugs after crashing his car.
- Duane owns a Mazda MX-5, which he is very protective over. Duane ends up crashing his car into one owned by a group of hooligans.
- Duane's Mazda MX-5 was actually owned by Simon Pegg.
- After stealing Tim's house keys in "Gone", Duane says "at last, I will have... revenge." This is a reference to a quote made by Darth Maul in Star Wars Episode I: The Phantom Menace. Peter Serafinowicz, the actor who plays Duane, was also the voice of Darth Maul.