Once Upon a Time is getting an extra episode this season thanks to a supersized effort airing during November sweep.

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Co-creator/executive producer Adam Horowitz announced on Thursday via his Twitter account that episode eight, titled "Smash the Mirror," will expand to two hours. Though it was originally said that the episode would begin airing an hour earlier, ABC on Friday confirmed that it will start at its regular time of 8 p.m. on Sunday, Nov. 16. Horowitz updated his followers on Friday.

Excited to tell ya ep 408 on 11/16 of #OnceUponATime is being expanded to TWO hours. Set to air an hour earlier from 7/6c til 9/8c on ABC — Adam Horowitz (@AdamHorowitzLA) October 23, 2014

To clarify, the special 2 hour #OnceUponATime episode is set to air from 8/7c to 10/9c on 11/16 -- same start time as usual! Hope to see ya! — Adam Horowitz (@AdamHorowitzLA) October 24, 2014

That means Once's fourth season will run 23 episodes instead of the usual 22, though it will still air in two 11-episode runs. Horowitz reassured that the extra hour will not be a special or a recap episode.

Once Upon a Time airs 8 p.m. Sundays on ABC.

Oct. 24, 1:12 p.m. Updated new time for two-hour episode.

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Twitter: @insidethetube