For half a century, Beach Boys songs like "Fun, Fun, Fun" have promised unending summers of fun in the sun -- not at all like the life founding Beach Boy Brian Wilson actually led for many years, as Anthony Mason tells us now in our Sunday Profile:

On a warm summer night at the Greek Theatre in Los Angeles last month, Brian Wilson -- backed by a band that included fellow former Beach Boy Al Jardine -- was running through his repertoire of classics when a cake was wheeled out from backstage by the extended Wilson family.

On this night, the man many regard as one of America's greatest living songwriters turned 73.

Well, East coast girls are hip,

I really dig those styles they wear.

And the Southern girls, with the way they talk,

They knock me out when I'm down there.

The Midwest farmer's daughters really make you feel alright.

And the Northern girls with the way they kiss

They keep their boyfriends warm at night.

I wish they all could be California

I wish they all could be California

I wish they all could be California girls.

-- "California Girls," by Brian Wilson and Mike Love (1965)

Wilson, who created the sun & surf sound that's still the soundtrack for the American summer, has had a summer of milestones. On tour again, he has just released his 11th solo album, "No Pier Pressure," and is the subject of a new film about his life, "Love & Mercy."

Brian Wilson and Al Jardine of The Beach Boys perform at the Greek Theatre in Los Angeles. CBS News

Mason asked, "How did you feel when you saw the film?"

"I was very happy to see the good parts," Wilson said. "But the dark periods were, like, very rough to watch."

Paul Dano and John Cusack each play Brian Wilson in "Love & Mercy." Roadside Attractions

John Cusack plays an older Brian Wilson, the artist struggling to recover from depression, mental illness and drug abuse. Paul Dano pays the younger Brian Wilson, the musical genius who dreams up the Beach Boys' intricate harmonies and orchestrations.

Wilson was just 20 when the Beach Boys signed with Capitol Records and made their first album in an L.A. studio.

Mason asked, "Do you remember recording in this room?"

"I remember recording 'If everybody had an ocean across the USA ...'" Wilson said.

He would create the most successful band in America, blending the voices of his brothers Dennis and Carl, cousin Mike Love, and close friend Al Jardine. "Mike on bass, Al and Dennis and Carl in the mid-range, and me on falsetto. We all sang together. And the harmony just happened."

"Love & Mercy" focuses on two pivotal points in Wilson's life: First, the recording of The Beach Boys' highly-influential "Pet Sounds" album in 1965, that featured "Wouldn't It Be Nice" and "God Only Knows."

"I was so proud of that album, I could have cried," said Wilson. "Very proud of it."

"Your father fought you about it, and the band fought you about it," said Mason.