DC's Legends of Tomorrow Season 3 Episode 11
Here I Go Again
On Legends of Tomorrow Season 3 Episode 11, the team returns from a mission to Zari having shut down Gideon and ruining the ship's abilities, and after an awful encounter with Captain Sara, Zari is sent on her way to fix Gideon and the Waverider... on her own.
However, things go awry when the ship explodes, leaving Zari to wake up in the exact moment Sara finished yelling at her (repeatedly, like, over 100 times). No matter what she does, Zari is stuck in the same hour aboard the Waverider, reliving the moment everyone on the ships dies, and she can't stop it on her own.
Needing an ally, Zari confides in Nate, over and over, and he's instantly brought into it with the memory of "Groundhog Day" and he doesn't question Zari once about whether she's telling the truth or not.
While searching for the bomb, Zari investigates every member of the team to see if someone could have accidentally set off the bomb, though it isn't until the team finds Gary in the trash compactor that Zari understands why there's a time loop.
In the end, the time loop was all a symptom of Gideon and Zari's simulator to get Zari to stay on the Waverider.