Yes, that was apparently Keanu in last night's Severance

Noted voice actor Keanu Reeves—you might know him as the voice of The Angry Hedgehog Who Owns A Gun in the recent Sonic The Hedgehog 3—popped back up on people's radars unexpectedly last night. So, yeah: If you were watching Apple TV+'s Severance, and found yourself asking, "Wait, is that…?" while watching the stop-motion "Macrodat Uprising" video Mark and his fellow Innies are forced to watch as part of their reintroduction to the show's dystopian world, you weren't just slowly being driven to madness by your eternal fractured existence. That really does seem to have been Keanu Reeves as the talking building.

Collider briefly talked to series creator Dan Erickson about the surprise cameo, for a sequence that was apparently the very first thing shot for the new season. (That's per the official Severance podcast, in which you can hear Ben Stiller get sidetracked with a very long plot description of The Year Without A Santa Claus while describing plans for the short.) Erickson wouldn't directly answer who else had been considered for the ear-catching cameo, but confirmed that, "All I can say is that we talked about a couple of different people for that role. We always wanted it to be somebody that people have certain associations with, but also, it had to be a very warm presence. The Lumon building is very friendly in the context of this video, and there’s a friendliness to that particular voice and a heart to that particular voice.” (No word whether similar consideration was given to the casting of SNL's Sarah Sherman as the talking water tower.)

Reeves has been getting more into the world of voice acting in recent years, possibly in deference to his poor, brutalized-by-a-life-of-kicks-and-slides knees; he previously had a notable voice role in Toy Story 4, and gave a mammoth performance in the video game Cyberpunk 2077.