Adam McKay on "The Big Short" and Oscar controversy

Writer, producer and director Adam McKay brought us hit comedies like "Anchorman," "Talladega Nights" and "Step Brothers." But his latest comedy tackles a darker issue and time in recent American history.

"The Big Short" follows the events leading up to the 2008 financial crisis from the perspective of four men who see what's coming before anybody else, including a tormented hedge-fund manager played by actor Steve Carrell.

"You know, we've always kind of called it a "tra-medy," McKay told "CBS This Morning" Tuesday. "I think there's some comedic elements to it."

But at the center of the film is what McKay called the "scariest moment."

"...To realize that all these professionals, all these people that are mathematicians, that are leaders, including all of us - I'm a member of the media as well... we all completely missed this. There was this sense that America could do no wrong," McKay said. "What was wrong with our popular consensual culture that we all missed this?"

McKay was inspired to make the film after reading Michael Lewis's nonfiction bestseller, on which the movie is based.

"I read it in one night and I just thought, 'I have not read anything like this where the characters are so compelling,'" McKay said. "I knew there were issues with the banks - there wasn't enough oversight. But (the) book just lit me up as far as really getting a human and informational perspective."

The story was also personal, as McKay had a close relative who lost a home and several friends who lost jobs during the crisis.

McKay said the comical twist helped portray the serious topic to the general public.

"So we sort of looked at popular culture and celebrity culture and have the idea of - 'What would happen if every time Kim Kardashian were on camera, she described the Libor rates scandal...?''" McKay said. "So it came from sort of poking fun at our celebrity culture and at the same time, wanting to convey information in a fun, light way because we didn't feel this was heavy material."

The director said big Hollywood stars in addition to Carrell - including Brad Pitt, Ryan Gosling and Christian Bale - also helped, especially because they were able to transform into the book's characters.

Off the movie set, McKay is also well-known for his humor, even among comedians. But the director said he was careful to tone it down at times while on the set.

"...There were some heartbreaking scenes in this movie and my instinct is always keep a playful set and there were times when I had to go, 'No, silence on this one,'" he said.

"The Big Short" picked up the top film award from the Producer's Guild of America last Saturday, and is now up for five Oscars, including Best Director nomination for McKay.

McKay commented on the uproar over the lack of diversity among the Oscar nominations, saying, "I 100 percent support the debate" and that directors and actors should welcome the discussion.

"I was sad to see some talented people not recognized. If our group of people, filmmakers, can't embrace this kind of debate, I think it is sad," McKay said. The director also welcomed the Academy's recent announcement of changes to promote diversity.

"At the end of the day though, I completely support it and I agree that there is a diversity issue right now in Hollywood," McKay said. "But I do have faith in our system that will fix it."