World, meet Mr. Hyde. Image: Universal

Though The Mummy stars Tom Cruise and Sofia Boutella, one of the most intriguing characters is played by Russell Crowe. The Oscar winner is Dr. Jekyll, a key figure in the new Universal Monsters film universe, and this new video reveals his dark side.

Reveals it quite literally, of course, because it’s Mr. Hyde, the evil side of the classic character. Hyde makes a brief appearance at the end of this video about The Mummy, which also explains how Jekyll and Hyde fit into its world.

The writer and director of The Mummy, Alex Kurtzman, previously explained that Jekyll’s group, Prodigium, is kind of the connective tissue within Universal’s planned “new world of Gods and monsters,” which includes movies about Frankenstein, Dracula, the Wolf Man, and others.

We wanted to understand the context of The Mummy in the larger world. And we wanted to know that monsters existed for millennia. And we knew that as the story evolved there was going to be an organization that was maybe cataloging them, following them, collecting them. That would determine the good ones from the bad ones. That was sort of the keeper of that secret history.

So to lead that group, they cast Russell Crowe as Jekyll, who’ll not only play a key role in The Mummy, but roles in other Universal Monsters movies in the future, whatever those may be.

The Mummy opens June 9.