Legendary entertainer Andy Williams reveals a shocking secret in his new autobiography – the wholesome, All-American singer says he dropped acid in the ’60s!

In his new memoir, Moon River and Me, the 81-year-old reveals he experimented with LSD as his marriage to Claudine Longet was crumbling.

Andy says that he and Claudine were blissfully in love when they married in 1961 and had three children – Noelle, Christian and Bobby. But Andy’s career kept him touring for weeks at a time, and by 1969, Claudine had grown tired of raising the children on her own, he recalls in the book.

After the marriage collapsed, Andy packed his bags and left, and focused his attention on his career – but he couldn’t escape nagging feelings that something wasn’t right with him. He had been under the care of a psychiatrist, but therapy didn’t seem to help.

"My life was in turmoil," he wrote.

He sought help at the famous Scripps Clinic in San Diego, he says, and his doctor there suggested LSD treatments to help him uncover the source of his chronic unhappiness.

Scripps discontinued their LSD therapy program before Andy’s first session, so he flew to Canada to receive the controversial treatment.

"The LSD was in liquid form, dripped onto a sugar cube or a tiny square of blotting paper," he wrote. "It was odorless, colorless and tasteless."

Andy remembers feeling nothing immediately after taking the first dose, but soon "shapes began shifting and changing, while colors and sounds intensified."

"I became absorbed in one object or sensation, totally unaware of anything else around me, but then I’d snap back to reality, spiraling in and out of awareness of my surroundings.

"LSD gave me powerful feelings of euphoria – some sex-related – but also a sense of fear and despair," he wrote. At one point, he says, he bizarrely hallucinated that he was going through childbirth.

"I’m not sure if LSD did me any good, but one thing came out of my stay at the clinic. It was probably the first time in years I had taken a few days away from my career," Andy says.

"I came to realize my children and my relationship with my family were the things that really counted."

Unfortunately, Andy writes, his revelation came too late. Although they remained close friends, he and Claudine divorced in 1975. Andy has been married to his second wife Debbie, 55, since 1991.