“Crisis on Infinite Earths” will take no prisoners, as seen in this emotional sneak peek from Part 1 of the Arrowverse’s crossover event, which kicks off this Sunday at 8/7c on The CW’s Supergirl.

In the premiere of the five-part crossover, The Monitor (played by guest star LaMonica Garrett) sends Harbinger (Arrow’s Audrey Marie Anderson) to gather the worlds’ greatest heroes — including Supergirl (Melissa Benoist), The Flash (Grant Gustin), Green Arrow (Stephen Amell), Batwoman (Ruby Rose), White Canary (Caity Lotz), The Atom (Brandon Routh) and Superman (Tyler Hoechlin) — in preparation for the impending Crisis. 'Crisis on Infinite Earths' Arrowverse Crossover Photos

Said Crisis, though, will soon lay waste to another world. And in the exclusive sneak peek above, Kara explains to her cousin Clark how she can somehow remain hopeful, even after they suffer devastating losses. Press play to watch the emotional exchange.

“There’s a lovely scene between Clark and Kara on the balcony, when they’re talking about legacies and how they move on from the destruction of Argo City at the beginning of the hour,” Supergirl EP Robert Rovner noted at a recent press screening of Parts 1 and 2.

Teasing other combos/convos, Arrowverse EP Marc Guggenheim says Kara will also have a conversation that is “so, so resonant” in Part 2, with Kate Kane aka Batwoman. “Then they have a scene in Hour 3 that sort of pays off the cliffhanger of [Hour 2] that is phenomenal. Melissa and Ruby just blow the doors off the place.

“Similarly, also in Hour 3,” Guggenheim continues, “there’s a great scene from Grant Gustin and Cress Williams (as Black Lightning).”

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