Smallville Exclusive First Look: Lex. Is. Back!

“They say every man has a dark side…. I am not every man. I’m Lex Luthor!”

And… goosebumps! The CW’s Smallville will wrap up its 10-year run the only way it really could, with Michael Rosenbaum reprising his role of Clark Kent’s arch nemesis, Lex Luthor — and we’ve got exclusive video promoting the big showdown.

Michael Rosenbaum Talks About Regaining His Lex Appeal

Press PLAY below to check it out, then catch your breath… catch your breath again…. and read on for more about the very super reunion:

Loading video...

Having Rosenbaum back for the series’ grand finale “was absolutely fantastic,” raves Smallville star Tom Welling, “because it was like he never left. We jumped right back into it.”

Coordinating the encore, however, was a veritable job for you-know-who, seeing as the deal was made late in the season and schedules had to be synched. As Rosenbaum recalls, “I called them up on like a Friday, saying: ‘Look, I want to do this, but I’ve go to film this other thing [Fox’s Breaking In] — so I’m coming up [to Vancouver] next Thursday.’ And they started writing!”

Or rewriting, as the case may be. “We had already started breaking the finale,” executive producer Kelly Souders tells TVLine. “But it was pretty easy and seamless to rev up that story faster.” After all, she notes: “It’s Lex!”

8 Reasons Why Smallville‘s ‘Booster’ Episode Is Golden

Though Clark does a bit of a double-take in the above clip, Souders says Lex’s second coming “is not going to be a complete shock” to those who knew and loathed him. In fact, injecting him into this final beat of Clark’s journey “will be very fun,” she promises.

Fun is precisely what Rosenbaum had as he slipped on a bald cap and returned to his very, very bad ways. “I really didn’t want the day to end,” the actor shares of his whirlwind, marathon shoot. “Once you’re there, you always want more. Like, ‘Oh c’mon, this is fun. Write something else!'”

The CW’s Smallville airs the first of its final four episodes this Friday at 8/7c.