'Shameless' Surprise: Former Series Regular Returns (Video)

Justin Chatwin makes a shocking comeback in the season-four finale.
Courtesy of Showtime

[Warning: This story contains spoilers from Sunday's season-four finale of Showtime's Shameless.]

A close member of the Gallagher family has returned.

During Sunday's season-four finale of Showtime's Shameless, former series regular Justin Chatwin made a surprising comeback as aka Jimmy (aka Steve). The character -- a con man who apparently is now going by the name Jack -- was presumed dead after the season-three finale but was seen with a character played by Dichen Lachman (Dollhouse) driving by the Gallagher household in the closing moments of the episode.

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Chatwin exited the series as a regular in June, with a rep for the cable network saying the door was left open for him to return for one or two episodes this season. But after the mystery regarding his whereabouts was not addressed early in the season, Jimmy's relationship with Fiona (Emmy Rossum) was not explored at all this year.

While it's unclear what kind of a role the actor will have in Shameless' previously announced fifth season -- his name was removed from the show's opening credits -- Chatwin's cameo would certainly indicate producers may have one in mind.

Jimmy was last seen during the season-three finale. The character spent the bulk of last season juggling his secret marriage to the daughter of a drug kingpin (so she could remain in the U.S.) and a domesticated life with Fiona.

When the drug dealer's daughter was deported after she couldn't reach Jimmy to continue the guise of their marriage of convenience, Jimmy was taken onto a boat by a thug, who later returned to hand Fiona an envelope stuffed with cash. Jimmy's presumed death was never seen onscreen. (The character in the past had a penchant for disappearing when the pressure became overwhelming, but he would always find his way back to Fiona.)

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News of Chatwin's return to the series was apparently kept a secret from the cast. Several took to Twitter late Sunday to reveal their surprise at the final scene of season four, where the actor -- who received multiple pilot offers this season -- returned.

"I guess it's not over till it's over," Chatwin wrote Sunday on Twitter.

Rossum -- as well as co-stars Steve Howey (Kevin), Shanola Hampton (Veronica) and Noel Fisher (Mickey) -- all tweeted their surprise, after finding out as the episode aired on the East Coast. (Showtime also did not release the episode early for review to the press as the cable network had done all season long.)

Rossum later explained that even she didn't know that Jimmy was alive. She wrote after speaking with producers and Chatwin that he was flown to Chicago and housed at a different hotel so none of the cast would know.

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During a TV season that has featured a slew of cast departures -- including characters played by Josh Charles, Sandra Oh, Taraji P. Henson, Rob Lowe and Rashida Jones, among countless others -- it's refreshing to see a beloved member of an underappreciated series return and have the twist remain unspoiled.

THR has reached out to Showtime for comment on Chatwin's status for season five. The network has not yet responded to requests for comment. Check out a video of Chatwin's return, below.

Email: Lesley.Goldberg@THR.com
Twitter: @Snoodit