The director of 'Ant-Man and the Wasp' says the shocking end-credit scene was influenced by secret details about the 'Infinity War' sequel

• "Ant-Man and the Wasp" director Peyton Reed explained how they decided on the shocking end-credit scene.
• He said one thing that helped was that he knew key things that will happen in the "Infinity War" sequel.

Warning: Spoilers ahead if you haven't seen "Ant-Man at the Wasp."

By now you probably know that something devastating happens during the end-credit scene of "Ant-Man and the Wasp."

Director Peyton Reed was able to make the whole movie light and funny, with pretty much no reference to the fact that at the same time it's taking place, the other Avengers are battling Thanos with half of humanity in the balance in "Avengers: Infinity War."

Reed told Business Insider that through much of the making of "Ant-Man and the Wasp," the amount they were going to address "Infinity War" kept changing. They finally landed on playing with the audience's knowledge of what happened in the previous MCU release by pushing it all aside, and just having fun telling the latest adventure of Scott Lang (Paul Rudd), Dr. Hank Pym (Michael Douglas), and his daughter Hope Van Dyne (Evangeline Lilly).

But when it came time to figure out what to do for the end-credit scene, which has become a tradition in MCU movies, Reed had to address "Infinity War."

Reed said the breakthrough moment on what to do came when he got some insight from the "Infinity War" sequel screenwriters.

"We went through all these different permutations and it so happened that Christopher Markus and Stephen McFeely were writing 'Infinity War' and 'Avengers 4,' so there were a couple of key things that we knew were probably going to happen in those movies which led to us being able to tee it up correctly in ours," Reed told Business Insider.

This led to what we see in the end-credits (STOP READING IF YOU HAVEN'T SEEN "ANT-MAN AND THE WASP"), Ant-Man stuck in the Quantum Realm while trying to retrieve quantum particles.

Turns out, when Ant-Man is about to be brought back to normal size by Pym, Hope, and her mom, Janet Van Dyne (Michelle Pfeiffer), after going subatomic to get into the Quantum Realm, the Thanos snap occurs in "Infinity War" and all three of them turn to dust. Ant-Man is left floating subatomic in the Quantum Realm with no way of getting back to normal size.

Reed said Markus and McFeely wrote a version of the end-credit scene, which he and his team then reworked.

"I was concerned that anything that happens has to be true, you can't do something to Scott Lang that feels out of character, so it was something that we had free rein to decide," Reed said. "Leaving Scott hanging literally and figuratively, that was something we knew we were going to do, but what else happens?"

Namely, who was going to survive the Thanos snap, other than Ant-Man, and who wasn't?

Reed said he was given full control of that decision and didn't have to coordinate with the executives at Marvel Studios. But, he was reminded by them that there was a little math involved.

"There's a certain percentage issue that's set up with Thanos' plan in 'Infinity War' and we had to deal with that," Reed said. "There was a point where we wondered how many of our characters are we going to have in that end-credit scene. Is Bill Foster (Laurence Fishburne) going to be there? Is Luis (Michael Peña) going to be there? That was part of our decision. We couldn't fudge this percentage issue too much. So there were all these issues that went into that decision. But we discussed it ad nauseam during the process."

We'll have to wait to see if in fact Dr. Foster and Luis did survive the Thanos snap, and how Scott Lang gets out of the Quantum Realm. But Reed said there was one certainty through all of this: the giant ant was going to live.

The second end-credit scene takes place back in Scott's apartment after the Thanos snap. The entire place is empty except for the giant ant, who during the movie has Scott's ankle bracelet on and impersonates his actions around the apartment so as not to tip off the authorities that Scott is out doing Ant-Man things. There are shots of empty rooms until finally there's a shot of the giant ant still playing the drums.

"We knew for our second scene we wanted to be more comedic than the first one, but we also didn't want to ignore the events," Reed said. "We were like, well, what if this ant just got used to living in Scott's apartment and found that he dug playing the drums? We were just like, 'This is really, really dumb and we love it,' and we put it in the movie."

"Ant-Man and the Wasp" is currently playing in theaters.

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