It’s not clear why this reel of behind-the-scenes Avengers: Age Of Ultron B-roll footage was posted to YouTube, nor is it clear why it’s so hypnotic to watch. But it is—to this writer, at least. The video plays out like a series of Vines from the set of Ultron, some with audio, and some without. Sometimes, the clips provide the reliable comedy of pre-CGI effects shots. At the 5:50 mark, for instance, Elizabeth Olsen unleashes some pretend Scarlet Witch hex bolts that will surely look amazing after post-production. And there are a few stunts that are impressive even without computer enhancement, like the two car-chase shots at the tail end of the footage. (For that matter, the car stunts might be even more startling in the sloppy verite style of this YouTube video than they will be once they acquire a clean cinematic sheen.)

But the best parts of this peculiar video might be the quiet snippets that show the workaday banality of moviemaking. There’s an ineffably calming effect to shots like Robert Downey Jr. flipping through script pages or Joss Whedon calmly giving directions on a green-screened Korean subway car. (“Now, you can change to the green line at Chungjeongno, but it’s easier to just take the purple all the way through to Wangsimni.”) Much like that mess of a Family Feud game we posted earlier today, the clips of on-set downtime lend a discordant note of relaxed, shaggy humanity to Marvel’s slick super-franchise. Except for the Jeremy Renner bits—apparently, he just always looks that intense.