SPOILER ALERT: This story contains spoilers from “Stuart Fails to Save the Universe” Season 1 Episode 3, now streaming on HBO Max.

Things get witchy in Episode 3 of “Stuart Fails to Save the Universe,” and a scary, 60-foot Bernadette (Melissa Raush) makes a guest appearance.

The aptly titled episode, “Spoiler: Bert Is Magic,” kicks off with Bert (Brian Posehn) tied at the stake and about to be burned alive. Then he begs for it to rain — and it does. That’s the first sign that in this universe, Bert really is a wizard with magical powers. He can turn regular Coke into Diet Coke at the flick of a wrist, and hocus pocus up a cute puppy.

Back in the comic book store (in this case, it’s called “The Wizard’s Sleeve” and more like a store filled with powerful, spellbinding books), Stuart (Kevin Sussman) tries to explain to the Denise (Lauren Lapkus) from last week’s universe what is exactly going on with the machine that’s transporting them across the multiverse.

Kripke (John Ross Bowie), who had seen Bert on the stake, makes his way back to the store. “Stuart, we have to leave here. The people in this world think science is evil.” Cracks Stuart: “How’s that different from our world?”