Sad news for 'Doctor Who' fans, as the beloved 11th Doctor, Matt Smith, has officially announced his decision to end the series. Smith's departure, of course, means the search has begun for a 12th Doctor to be introduced at the end of the year, but what does series showrunner Steven Moffat have to say about Smith's leave?

After months and months of back and forth, it seems Smith has finally decided to retire his Sonic Screwdriver. Today, he announced plans to make the upcoming Christmas special his last appearance in the role, following the upcoming 50th anniversary special with returning 'Doctor' David Tennant. Says Smith of his departure in a press release:

'Doctor Who' has been the most brilliant experience for me as an actor and a bloke, and that largely is down to the cast, crew and fans of the show. I'm incredibly grateful to all the cast and crew who work tirelessly every day, to realize all the elements of the show and deliver 'Doctor Who' to the audience. Many of them have become good friends and I'm incredibly proud of what we have achieved over the last four years.

Having Steven Moffat as showrunner write such varied, funny, mind-bending and brilliant scripts has been one of the greatest and most rewarding challenges of my career. It's been a privilege and a treat to work with Steven, he's a good friend and will continue to shape a brilliant world for the Doctor.

The fans of 'Doctor Who' around the world are unlike any other; they dress up, shout louder, know more about the history of the show (and speculate more about the future of the show) in a way that I've never seen before, your dedication is truly remarkable. Thank you so very much for supporting my incarnation of the Time Lord, number Eleven, who I might add is not done yet, I'm back for the 50th anniversary and the Christmas special!

It's been an honor to play this part, to follow the legacy of brilliant actors, and helm the TARDIS for a spell with 'the ginger, the nose and the impossible one.' But when ya gotta go, ya gotta go and Trenzalore calls. Thank you, guys. Matt.

Moffat had his own contributions to add on Smith's tenure as the Doctor, as well as the upcoming search for his replacement:

Every day, on every episode, in every set of rushes, Matt Smith surprised me: the way he'd turn a line, or spin on his heels, or make something funny, or out of nowhere make me cry, I just never knew what was coming next. The Doctor can be clown and hero, often at the same time, and Matt rose to both challenges magnificently. And even better than that, given the pressures of this extraordinary show, he is one of the nicest and hardest-working people I have ever had the privilege of knowing. Whatever we threw at him - sometimes literally - his behavior was always worthy of the Doctor.

But great actors always know when it's time for the curtain call, so this Christmas prepare for your hearts to break, as we say goodbye to number 11. Thank you, Matt - bow ties were never cooler.

Of course, this isn't the end of the story, because now the search begins. Somewhere out there right now - all unknowing, just going about their business - is someone who's about to become the Doctor. A life is going to change, and 'Doctor Who' will be born all over again! After 50 years, that's still so exciting!

We'll bring you the latest on the search, but what say you? Are you sad to see Matt Smith leave 'Doctor Who' after four years? Who do you think Steven Moffat will bring in to replace him? Give us your predictions for Matt Smith's final 'Doctor Who' appearances, and fondest remembrances in the comments!

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