Love & Mercy tells the little-known story of Beach Boys co-founder Brian Wilson and ET got the man himself to open up about the biopic!
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"I thought it was well done and very factual and portrayed very well," Wilson told ET at the Wednesday premiere.
In the film, John Cusack and Paul Dano carry the dual role of portraying the pop icon, whose immense success came at a terrible price. Dano plays a younger Wilson at a time when he starts to lose his grip on reality while creating some of the most influential songs of all time.
Older Wilson (Cusack) finds himself trying to escape the care of psychotherapist Eugene Landy (Paul Giamatti) with the help of his girlfriend and future wife Melinda (Elizabeth Banks).
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"I think we're letting people in on what happened to Brian and where he was and we're shining a light on the shame of mental illness and the mistreatment of those who were mentally ill for so long," Banks told ET.
Wilson credits his wife with saving his life by getting him out of Dr. Landy's program.
"The first time I saw [Love & Mercy] I totally didn't know what to think," his wife told ET. "I said, 'I have to go!' because it was so emotional."
Brian and Melinda are still married after 20 years and he's reconnected with his daughters Wendy and Carnie from his first marriage to singer Marilyn Rovell.
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"It's going to be heartbreaking for me," Carnie told ET. "I just love him so much and I'm glad we're here to celebrate him, his music and maybe to get a little more into the mind of Brian Wilson."
Love & Mercy opens June 5.