The Zigerions are notorious for being con artists of the highest order, scamming various alien species throughout the known galaxies. They've encountered Rick several times before, all with the intent of securing his secret recipe for concentrated dark matter. Being the clever jerk that he is, all Rick's ever given them was a faceful of his own naked butt (largely due to the Zigerion's squeamish aversion to human nudity.) But Prince Nebulon vows to have the last laugh.
The Zigerion's latest plan has Rick waking up in a simulated world they created. It nearly captures Rick's hometown, but is just off enough that he takes notice. Rick overloads the simulation until it's frozen, and then escapes with Morty. The duo reach Rick's garage, but it turns out to be yet another simulation, a plan Nebulon put forth knowing Rick would outsmart them the first time. The Zigerions gloat, claiming they already had the recipe for concentrated dark matter, and all they got out of this was the combination to Rick's safe. The safe contains Rick's secret projects, prompting the old man to hightail it out of there so he can change the combination before the Zigerions get to it. The Zigerions madly pursue them, forcing Rick's hand. Because concentrated dark matter boosts space travel, Rick desperately orders Morty to concoct a batch. Unfortunately Morty turns out to be fake and the entire chase was a simulation within a simulation within another simulation. The Zigerions finally pull a fast one on Rick, obtaining the recipe after so long.
After humiliating Rick, the Zigerions send him home. As they celebrate, Nebulon recreates the formula, only for their ship to blow up with them in it. Turns out Rick knew their plan all along and had given them a fake recipe. The lesson to take in all this: do NOT mess with Rick.