Jim Carrey revealed what helped him survive 'Grinch' role

Jim Carrey has opened up about the extreme measures he took to endure his transformation into one of his iconic roles.

Carrey gave rare insight into behind-the-scenes of the preparation it took to play Grinch for Ron Howard’s 2000 holiday classic Dr. Seuss’ How the Grinch Stole Christmas.

Carrey previously confirmed that he worked with a former CIA trainer to withstand the punishing hours in heavy makeup and an itchy yak-hair suit.

The actor recalled spending between three and eight hours in the makeup chair each day.

The make-up would be followed by long shoots in oversized prosthetic fingers, fake teeth, and tunnel-vision contact lenses.

The discomfort was so severe that Carrey suffered panic attacks.

At one point, The Mask actor told Howard and producer Brian Grazer he was ready to quit.

He even offered to return his $20 million paycheck.

"I will give all my money back. I'll pay interest. But I quit," Grazer recalled, in an interview, Carrey saying.

To keep him on board, Grazer enlisted Richard Marcinko, a former U.S. Navy SEAL commander who trained CIA operatives in torture endurance.

Marcinko coached Carrey through techniques to manage the stress, including physical distractions like punching his leg, rearranging objects in a room, and listening to the radio.

Carrey even smoked cigarettes with a long holder to avoid setting the yak hair aflame.