Castiel would surely approve of Eliot Ness, Misha Collins’ guest role on Timeless. In Monday night’s penultimate episode, called “Public Enemy No. 1,” the Supernatural star hops over to Supernatural creator Eric Kripke’s freshman adventure drama to play the man who brought down notorious Chicago gangster Al Capone and chronicled his life of law enforcement in the autobiography The Untouchables.

When the Time Team’s own Public Enemy No. 1 Flynn (Goran Visnjic) lands in 1931 Chicago to ask for help from Capone, Lucy (Abigail Spencer), Wyatt (Matt Lanter), and Rufus (Malcolm Barrett) will approach Ness in hopes of stopping both notorious villains. Below, Collins discusses switching from playing an angel to playing a lauded lawman.

ENTERTAINMENT WEEKLY: So you worked with Eric again for this. How did he approach you about hopping over to his new show for an episode?

MISHA COLLINS: He reached out by saying, “Hey, any interest in coming on to Timeless to play Eliot Ness?” And I said something like, “Send me the scripts!” But the truth is I would do anything for Eric Kripke, and I will say that until I meet my demise. I hope that after this turn as Eliot Ness, I haven’t poisoned the well and that he will call on me in the future, and if you publish this, and if you’re reading this, Eric, consider this groveling for future possible employment.

I doubt you poisoned the well. How familiar were you with Eliot Ness’s story and this era of mobsters? You went to the University of Chicago — did you pick up an appreciation for the Untouchables when you were there?

Yeah, I think as a graduate of Chicago, there’s something in the water there a little bit, but I’m not sure where I picked up on mobster history. I’ve been well aware of it for a long time. It’s just a fascinating part of American history and one I know a little bit about.

What did you do to research the role? Did you watch The Untouchables?

Well, I started where all good researchers start, which is Wikipedia. [Laughs] I discovered pretty quickly that there’s not a lot of footage or audio of Eliot Ness, so there wasn’t a ton to go on of actual primary source material. Kevin Costner’s portrayal I looked at briefly and then quickly determined that whatever he was doing I didn’t want to do. [Laughs] And then I just picked up some stuff and tried to piece something together. I tried to make him a little bit more of a badass, maybe. The real Eliot Ness is a bit more refined. Whatever. [Laughs] It’s television!

How did working on Timeless compare to working on Supernatural?

It’s fascinating, super high production value. I mean, it’s an incredibly challenging show because of this. I told the EPs of Supernatural the other day, I said it felt like coming back to work on a little student film because our show couldn’t compare. I mean there are all kind of VFX and big sets [for us], but to create worlds from another time from episode to episode is a truly epic undertaking, so it was very cool to see.

It was fun to put on some different clothes. I’ve been primarily wearing the same wardrobe for the last 10 years with a few exceptions, you know [laughs], so I was looking forward to changing. It’s funny, as an actor you never ever expect to be working on one thing for a decade, and it’s such a blessing to say that I’ve been working on a show that’s been going on 10 years, but it’s also thrilling to sneak out of those boots and be something else as well. And to do that with old friends was cool. There are crew members from Supernatural that have moved on to Timeless, so it was a bit of a reunion of sorts.

For the Supernatural fans, are there any Easter eggs they can look out for this episode that you and Eric may have inserted?

Oh, you got me. I can’t believe it, but I think we totally dropped the ball with [including] a Supernatural Easter egg. What they can look for is I will be wearing a trench coat and grimacing much like I do as Castiel, so there will certainly be echoes of another character in this episode.

Well, just for fun, what would a crossover between these shows look like?

Oh man, that would be amazing. I mean, they’re completely different universes and on completely different networks [laughs] but it would be amazing. Like I said, the trench coat could potentially be the crossover element. [Laughs] Oh, I wish we could have talked before I shot this, I would have brought my trench coat over from Supernatural and worn it on Timeless as Eliot Ness. That would’ve been the trick.