Geek internet is all aflutter with speculation that John Barrowman will be making a ‘surprise’ return to Doctor Who, driven largely in part by comments from Barrowman himself that he is in Cardiff in about a week and a half and he’s “not telling you what for…sssh!”
So, this is definitely him coming back to Who, right? I mean that makes sense, like the Radio Times article linked above points out, Captain Jack was first introduced in “The Empty Child,” the first DW episode penned by departing showrunner/person-that-someone-will-inevitably-comment-their-hatred-for Steven Moffat. Jack was also the primary protagonist in the Torchwood series that new showrunner Chris Chibnall was like totes involved with as well. The timing couldn’t be better for a return of the super queer charismatic Captain and potential Face of Boe.
But of course other possibilities have been suggested. It could be an episode of new Whoniverse series Class, or it could be some secret new Torchwood project. I do hope to see Captain Jack on Class, but I feel like it being a new show, the BBC would be all over the announcement that one of the most popular characters in modern Who is going to be on it. This is the company that holds actual special events to announce cast changes. A surprise return of Torchwood also feels unlikely for that same reason, no hyping press releases.
Barrowman knows exactly what mentioning being in Cardiff conjures up in the minds of his fans, and that this is a HUGE thing to tease. So unless there’s some third other option that we simply haven’t considered, something that will just be the best day ever, if he’s not coming back to Who he basically became that uncle who promised you a Sega Genesis for Christmas but really just has a drinking problem.