James Gunn questions audience response to Superman's Krypton message: "How can someone not think it's real?!"

DC boss James Gunn has finally cleared up one Superman detail that fans have not been able to decide if it is real or not – Superman’s Kryptonian parents’ message.

"How can someone not think it’s real? I don’t understand," said Gunn in an interview with Josh Horowitz on the Sad Happy Confused Podcast. "So, in the test screenings people were like ‘is it real?’ you know, AI, nobody trusts anything."

At the beginning of the movie, we learn that Superman is protecting the people of Earth, as that is what he believes his real parents, Jor-El (Bradley Cooper) and Lara (Angela Sarafyan), sent him down from planet Krypton to do. He listened to the message every time he heals from the yellow sun, because it "soothes him," as described by his robots.

However, the second half of the message was "damaged in transit" and was never heard, until The Engineer was able to retrieve it. Lex Luthor then broadcast its shocking contents to the world, which states that Jor-El and Lara really sent Superman down to 'protect' Earth so that he could rule over it and take as many wives as he could, as according to them, humans are simple and easy to control.

However, when the real message is shared with the world, Superman doesn’t quite believe it is real, and neither did a lot of real-life audience members during opening weekend. But thanks to Gunn, now we know for sure that it is very much real, and we had a lot of clues throughout the movie to prove so. "In the movie, Mr Terrific says I know those computer forensics guys, there’s no way. That’s Mr. Terrific, he’s as smart as Lex Luthor. Then, I have Mori, the secretary of defence, say 'Think whatever you think about Luthor, it’s real,'" said Gunn.

"And then the clincher is that Glarkos and Lex are walking together and Glarkos says 'Ah, you doctored the message, this is great' and Lex says 'It’s not doctored, it’s real, and who thought his own parents would be the ones to bring him down?'"

By the end of the movie, Superman has accepted that the message from his birth parents is very much real. However, he realizes that he does good because of his own beliefs and because he was raised by two very kind-hearted people, Jonathan and Martha Kent (Pruitt Taylor Vince and Neva Howell). Instead of listening to his Krytonian parents' message while he heals, he now watches a reel of his rural and very happy upbringing with his adoptive parents in Smallville, Kansas.

"At the heart of it, this is a story about a guy who is doing things he thinks for reasons outside of himself. He comes to realise, through the love of a parental figure, that he is not doing thing because of something outside of himself, he’s doing things because that’s what he believes," explained Gunn. "It’s not destiny, it’s his own choice."

Superman is out in cinemas now. For more, read our Superman review, check out our guides on Superman ending explained and Superman Easter eggs, and keep up with the upcoming DC movies that are currently in the works.