The following post obviously contains SPOILERS for Avengers: Infinity War. You really should hurry up and see this movie soon before someone accidentally spoils it for you.

Even with fan anticipation at a fever pitch, dozens of cast members and literally thousands of crew members (6,000 is the figure I’ve heard), Marvel managed to keep the shocking ending of Avengers: Infinity War a secret until the movie was released. Just how good was Marvel at keeping the surprises hush-hush? Even the actors had no idea who was going to live or die until the day they shot the infamous Thanos snap scene.

It seems impossible, but that’s what we’re told on the new Infinity War Blu-ray. In the special feature “Beyond the Battle: Wakanda,” Infinity War executive producer Trinh Tran describes the process:

The blip-out sequence, we had gathered the whole entire talent there, circled around our directors, and basically revealed to them that morning of, when they came on set, that that scene was happening, that some of them were going to be, you know, disappearing.

There’s a very brief soundless clip of the Russos directing the actors; based on their movements it looks like they’re describing what it’s going to look like when the Avengers get erased from existence. But I hope after Avengers 4 comes out we get to see more of the BTS footage from this day on set. I want to see how Chadwick Boseman reacted when they told him “Hey I know Black Panther looks like it could be big, but you’re dead. Sorry. No sequel.”

Even if the actors were surprised, it wasn’t for long; they’ve already shot Avengers 4, so however their “deaths” are resolved, they already know. Still, we would love to see the actors’ expressions when the Russos told them about how this scene was going to go down. Avengers: Infinity War is available on Blu-ray now (or Digital HD, if physical media is already dead to you).

Gallery - 15 Movies You Didn’t Know Inspired the Marvel Cinematic Universe:

More From ScreenCrush