As per usual, Stern was able to draw a few big revelations from the 55-year-old actor, who didn't hold back when it came to discussing his non-belief in marriage, his "fake" agent and details about some of the biggest roles he missed out on playing in the past.
With that being said, here are the 7 biggest bombshells Grant revealed during the interview:
1. He Created a Fake Agent for Himself: "I do have an agent again now, but I did for four years not have one," the actor explained, revealing that he would tell people who were interested in working with him to reach out to a man named James Howe Ealy.
"He didn't exist. It was me on a different email account," Hugh continued. "I saved myself an absolute fortune."
However, he eventually started running into trouble when people would ask to speak with him on the phone or meet with him in person. He also accidentally signed off as "Hugh" a couple times after too many drinks, encouraging him to go back to his old agent.
2. He Doesn't Believe in Marriage: "I can see the lovely aspect if you marry exactly the right person—your best friend and it's cozy and it's lovely. But, people make so many mistakes," Grant, who has never been married, admitted to Stern. "Do I think human beings are meant to be in 40-year-long monogamous, faithful, relationships? No, No, No. Whoever said they were? Only the bible or something. No one ever said that was a good idea."
He added, "I think there's something unromantic about marriage. You're closing yourself off."
3. He Believes Extramarital Affairs Might Actually Help Marriages: His character in Florence Foster Jenkins has a mistress in the movie, and he admits that he "likes " it.
"I always admire the French and the Italians who are very devoted to their marriages," he explained. "They take them extremely seriously, but it is understood that there might be other visitors at 5 o'clock in the afternoon. You just never boast about. They never say anything, but that's what keeps marriages together."
"The problem was they didn't have a script for the new character," he explained. "They just said, 'Trust us, we'll create one.'…They make brilliant TV shows, but I said, 'I'm too scared to sign up without a script.'"
5. Ang Lee's Interesting Form of Directing: Lee directed Grant in Sense and Sensibility, and at first, the actor admitted he was a little difficult to work with.
"He comes from a tradition in Taiwanese film making where the director is king," Grant explained. "Someone literally follows them with a chair behind their bottom in case they want to sit down."
As they continued working together, though, Grant's opinions changed. "I loved him in the end. He's actually quite good."
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6. He Turned Down What Could Have Been the Biggest Role in His Life: "I used to boast in interviews, 'Ah, you know. I'm not necessarily the greatest actor in the world, but I am really good at choosing material. I have never turned down something that turned out to be a success,'" he recalled. "As soon as I started saying that, I turned down a film that went on to be the biggest success, biggest hit, for the part that I turned down for that actor."
He continued, "The honest truth is, I probably wouldn't have been as good as the guy who did it. He did it brilliantly. It's a source of great misery to me."
7. He Basically Played a Real-Life James Bond: During the phone hacking scandal in Great Britain, Grant got very involved and became an advocate for personal privacy.
"The last five years of my life have all been about politics," he admitted to Stern, expressing his disbelief in the media's invasion of privacy at the time. "They were allowed to do it with impunity. The police were paid off, wouldn't come after them. The government looked the other way because government in Britain is so terrified of these few big newspaper bosses."
Thus, Grant took it upon himself to catch one of the reporters, wearing a spy pen with a microphone to record a conversation, which he then released and transcribed for a magazine to reveal what media outlets were doing to obtain information.
He's Been Fat Shamed: "I was fat shamed the other day on a British newspaper," he revealed to Stern, explaining how photographs were taken of him in Southern Spain during a trip with his children. "The headline was 'Four Bellies and a Turkey Neck.'"
He admitted, "They weren't wrong. I looked shocking. It was awful...I hang off a strap every morning [now] called TRX."