Supergirl: Alex's Coming Out Speech Is Interrupted By a Surprise Guest

The "Supergirl" clan will celebrate Thanksgiving a little late this year, with the Danvers family and friends sitting down for some turkey on Monday for the start of the four-night "Arrowverse" crossover event.

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In a new preview clip, which you can watch at TVLine, James Olsen and Winn Schott suck up to Kara while Mon-El enjoys his first Earth Thanksgiving. The guests don't get to enjoy their meal, however. Alex seems to be just about ready to come out to her mom when the group is interrupted by a burst of light, one of the first signs of the impending alien invasion.

The "Supergirl," "Flash," "Arrow" and "DC's Legends of Tomorrow" crossover will feature The CW heroes teaming up to fight the Dominators, mind-controlling aliens intent on stomping out Earth's metahuman threat before it can reach outer space.

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The crossover will start Monday, Nov. 28, on "Supergirl," before moving to "The Flash" on Tuesday, "Arrow" on Wednesday and concluding on "DC's Legends of Tomorrow" on Thursday.

Airing Mondays at 8 pm ET/PT on The CW, "Supergirl" stars Melissa Benoist, Mehcad Brooks, Chyler Leigh, Jeremy Jordan, David Harewood and Chris Wood.

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