With the theatrical debut of Spider-Man: Homecoming just days away, Heat Vision unearthed a candid interview Lee gave in 1977 when he said DC had a lot to learn about what people wanted from a comic book character.

"Miserable" is the word Lee used to describe DC during the interview. "They've been trying to catch up," he said. "They're doing the best they can, bless their innocent little hearts. We used to have a lot of fun with them when we started outselling them."

Lee said he and his staff had friends who worked for DC, and they would tell their Marvel pals how DC staff would have big meetings to try and crack why Marvel was moving more books.

"They studied our books, and they'd say, 'You know, I noticed they use a lot of red on their covers. Maybe that's it,'" Lee said in the vintage interview. "And they would start putting a lot of red on their covers. The minute we would learn of that, we would take all the red off our covers. And our books still sold better, and that would drive them crazy."

When the color theory didn't pan out, Lee said DC assumed Marvel's success must be linked to the abundance of dialogue bubbles on the covers, so Marvel did away with those.

"It never occurred to them that we take the work a little more seriously and maybe we have a little bit more of a sense of humor," he said. "And maybe people don't like things that are a little bit stuffy. They like things that are whimsical or humorous."

Lee concluded his thoughts by joking with the interviewer to not repeat what he said to DC: "That's just between us."

Lee did not specify what time period he was speaking about, but the once-struggling Marvel did surprise the comic book industry when it began outselling DC in the mid-1960s, thanks in large part to the colorful, interconnected universe of characters such as Spider-Man, Fantastic Four, The Avengers and X-Men created by Lee and artists such as Jack Kirby and Steve Ditko.

Spider-Man: Homecoming opens Friday. Lee has a cameo in the Sony/Marvel picture.