WARNING: The following article contains spoilers for "Fugitive of the Judoon," the fifth episode of Doctor Who Series 12.

After years away from the franchise, John Barrowman has finally made his return to the world of Doctor Who, appearing in fifth episode the long-running British sci-fi series' 12th series, "Fugitive of the Judoon."

Barrowman made his debut as the character Jack Harkness in 2005's two-part Doctor Who story "The Empty Child" and "The Doctor Dances." Barrowman's Jack returned in 2006 as the lead character of the spinoff series Torchwood, which ran for 41 episodes across four seasons, concluding in 2011. In addition to the television series, Torchwood has spun out into such mediums as comic books, novels, e-books and radio dramas.

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Ever since Torchwood's conclusion, Barrowman has campaigned hard for the return of Jack Harkness and company. He finally got his wish in "Fugitive of the Judoon," in which the character shows up to deliver a message to Jodie Whittaker's Doctor. (Fitting, considering he already made one major return earlier this week, reprising his role as Malcolm Merlyn on The CW's Arrow as part of "Crisis on Infinite Earths.")

Ahead of the Doctor Who episode's initial airing, Barrowman took part in an interview with Radio Times. "It feels absolutely amazing," Barrowman said of his reprisal. "I’ve always been holding the torch to eventually bring Jack back, because I know the love that the fanbase and the Whovians around the world have for him. Without giving too much of the story away, it's the same Jack you know. He's flirtatious, he's sassy, he's also determined. So, Hallelujah -- Jack is back!"

Barrowman elaborated, "I wouldn’t say vindication is the word. I’d say that I’m glad. I’m really chuffed by it. Put it this way -- there’s a little grin on my face! They wanted to keep it fresh, but also this is probably one of the biggest returns, if I can say so myself.

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"The internet is going to blow up," he continued. "Because as soon as he appears onscreen… everybody in the U.K.’s going to tell everybody in the U.S., and the US. .is going to tell everybody in South America. Then it’s going to go to China, and then it’s going to go all over the place. The whole world is going to go mad. I hope -- I could be wrong -- but I hope that Jack is trending worldwide when it happens."

Barrowman is currently not dishing on what -- if anything -- Jack's return in Doctor Who's latest episode could mean for the future of the series, or the future of Torchwood. Furthermore, he isn't exactly sure why the decision was finally made to bring him back. All the same, he's glad it was. "Who knows what the decisions were and why they were made," he said. "But I’m glad they were made, and if I can say so personally -- it’s about time."

Doctor Who stars Jodie Whittaker as the 13th iteration of the titular Time Lord. Whittaker is joined by co-stars Bradley Walsh, Tosin Cole and Mandip Gill in a series spearheaded by showrunner Chris Chibnall. The next episode is set to air on the BBC on Feb. 2. The new season and all previous 11 seasons will stream on HBO Max later this year.

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