Gilly bids a final farewell to the village next week after the show's long-running rape storyline reaches its conclusion.
Although Gilly was found not guilty of raping Jacqui McQueen earlier this year, events will soon take a new twist in a special three-hander episode, which sees him pay an emotional visit to the barmaid and her husband Rhys (Andrew Moss). Following an intense discussion, Gilly decides to move away for good.
Reflecting on his last day on set, Quinlan told Inside Soap: "It was always going to be a sad time. The cast put together a 'bible' of everything Gilly's done over the years, and I've taken a few of his clothes to remember him by. I'd never wear them myself, though - he wasn't exactly the best-dressed guy in the village, was he?
"I'd never say never about returning to Hollyoaks, but at the moment it's time to move on. You're not going to get a much better education than being in a show like that - it's been amazing."
The actor has appeared in two plays at The Lowry theatre in Manchester this year, including a recent role in The Lonely Clouds of Guernica.
Meanwhile, part of Hollyoaks' upcoming three-hander episode sees Gilly make an apology to Jacqui (Claire Cooper) over what happened between them on Valentine's night.
Quinlan said: "I can't give too much away about what takes place when he arrives at their flat, but something happens to make him question whether he did take things too far with Jacqui. It's just absolutely heartbreaking."
Hollyoaks' Gilly, Jacqui and Rhys three-hander airs on Friday at 7pm on E4 and next Monday at 6.30pm on Channel 4.
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