Matt Smith On His 'Doctor Who' Departure And His Possible Return To The Show At Comic-Con (VIDEO)

This will likely be Matt Smith's last Comic-Con as the titular character in BBC's long-running hit "Doctor Who" and the actor is struggling to say goodbye. At Entertainment Weekly's Brave New Warriors panel (above), which also included Tyler Posey ("Teen Wolf") Kit Harington ("Game of Thrones"), David Guintoli ("Grimm") and Steven Yeun ("The Walking Dead"), the actor opened up about leaving the show after the 2013 Christmas special at the end of the year.

"It's been four years and the best four years. It's been wonderful. It's been a privilege to work with [executive producer] Steven Moffat, but I think, 'When you got to go, you go to go,'" Smith explained to the crowd, eliciting many exclamatory sounds from the audience. "It's sad and I'm going to miss it. I'm going to miss Comic-Con -- I love Comic-Con. The world should be more like Comic-Con. It wasn't an easy decision to come to, but ... you can't play it forever. And look, they'll get someone amazing [to play the Doctor]. They'll get someone brilliant to do it. They really will. And that's the great thing about the show is that it continues, and the strength of it survives, and it'll get better, and it'll get bigger, and it'll keep up, and you'll forget about me." Cue even more "no's" and "aw's" from the crowd.

Smith went on to say that he's having trouble hearing about how "Doctor Who" will go on once he's left. "Steven Moffat was actually pitching all the episode ideas for next season to me last night -- that was really hard," he admitted.

When asked what he would want to do if he were to return to "Doctor Who," Smith replied, "I'd always wanted to do an episode based on Sinatra ... or Atlantis."

But no matter how hard hearing about "Doctor Who" may be or whether or not he'll return, Smith said he'll always watch. "I'm a big fan as well as being in it," he said. "I'll follow it and they'll get a brilliant actor [to play the Doctor next]. To know it carries on is kind of lovely -- you're part of a legacy that doesn't die ... I'm a little cog in a big wheel. I'll keep watching for sure."

Check back with HuffPost TV on Sunday, July 21 for more on "Doctor Who" from the show's 50th Anniversary panel.

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