In this world, Castle never met Detective Kate Beckett. As a result, Beckett's mother's murder was never solved, and she never found happiness. She is a hardened, isolated Captain of the 12th Precinct who treats Castle like a complete stranger.

In stark contrast to the gritty sci-fi of Rick and Morty , the procedural drama Castle used an alternate universe to examine its central romance.

The episode breaks outside the "Central Finite Curve"—the walled-off portion of the multiverse where Rick is always the smartest man alive—to show how actual multiversal travel operates without Rick's totalitarian boundaries.