UPDATED: The special episode, "The Day of the Doctor," premieres on Nov. 23.

BBC has released the trailer for the 50th anniversary special of Doctor Who.

The anticipated program, titled "The Day of the Doctor," airs on Nov. 23 in the U.K. and U.S. Another teaser had been screened at Comic-Con in July but not released online.

"Now is the time to face the choices I've made in the name of the Doctor -- our future depends on one single moment of one impossible day," goes the narration by Matt Smith.

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Watch below: