Dennis Wilson, left, the drummer for the Beach Boys in 1966, and convicted murderer Charles Manson in 1981. (AP photos)

In the summer of 1968, at the height of the sex, drugs and rock ‘n’ roll era, Beach Boys drummer Dennis Wilson welcomed into his orbit an unknown and peculiar long-haired rocker who sang wildly and talked mystically.

“This is Charlie,” Wilson told friends. “He is the wizard, man. He is a gas.”

Charlie was Charles Manson, who would orchestrate seven murders the next year and who died in prison Sunday night at 83.

Wilson went the rest of his life not speaking of the months he spent with that guy Charlie and his followers dropping acid, enjoying group sex and jamming late into the night. “As long as I live,” Wilson told Rolling Stone, “I’ll never talk about that.”

But among the many surreal episodes of Manson’s life, that summer marked a key moment in cementing his persuasive powers over his so-called family, whom he would direct the following summer to brutally and ritualistically kill actress Sharon Tate and six others — murders that shocked the country and made Manson infamous.

“Charlie told us that all we had to do was ask the universe for what we wanted and it would be presented,” Dianne Lake, a “family” member who didn’t participate the murders, wrote in a recent memoir. “In the connection with Dennis Wilson, it appeared that was precisely what had happened: Charlie had led us to the communal promised land — everything he’d asked for had come to pass.”

There was music, there was sex, there were drugs.

“We were living free of hang-ups, with no more worries about where stuff was going to come from,” Lake wrote. “Our anti-materialism and practice of living in the now were working. Charlie’s beliefs … were being validated more and more each day. Just the fact that he’d been able to captivate someone as famous as a member of the Beach Boys was proof enough.”

The whole episode was an accident, of sorts.

Early that summer, Wilson was driving down Sunset Boulevard when he spotted some hitchhikers — two young women who, it turned out, were members of Manson’s cadre. He offered to drive them home. Along the way, the women told Wilson that this man they were living with, a musician named Charlie, was their spiritual guru. Wilson, seemingly lost amid an ugly divorce and the trappings of fame, wanted to meet him.

In a sense, Wilson was trapped, Lake wrote:

Dennis and Charlie hit it off right away, which is not surprising, given Charlie’s skills at ingratiating himself with strangers. Dennis, in no rush to leave, hung out for a while, smoked some pot with Charlie, and listened a bit to Charlie’s songs. It was obvious from the start that Dennis liked the girls and admired Charlie’s harem. We sat at Charlie’s feet and looked at him lovingly as he sang and played guitar. We made sure Dennis saw how much we idolized Charlie — we knew that was our job, without Charlie even having to tell us.

Manson picked up a guitar and started playing. Wilson was entranced.

“Charlie played guitar well enough, and Dennis, a self-taught drummer, hardly played at all, so Charlie began to show him how,” Lake wrote. “Watching them together, we could see they’d connected with each other. Dennis’s good looks gave him the kind of magnetism perfect for Charlie, but as it turned out, Charlie quickly keyed into his soft spots.”

Within days, Manson and his family were living with Wilson, who provided for their every need. When a nasty strain of gonorrhea invaded the home, making group sex painful and not particularly joyous, Wilson took everyone to the doctor for treatment. And Manson and his family provided what Wilson needed at that moment — a sense of freedom, wonder and adventure.

“That is how,” Lake wrote, “we wound up driving in Dennis’s burgundy Rolls-Royce to the back of a grocery store and showed him the art of Dumpster diving.” She writes:

We all laughed and sang all the way to the Dumpster, dragging Dennis by his hand. The best thing we found on this run was a flat of strawberries. After culling out the bad ones, we had enough to make him a strawberry cake complete with fresh Cool Whip. Charlie was leaning against the Rolls watching as we showed Dennis how it was done. “Dennis, do you know how much good food is thrown out in America?” he shouted. One of the girls popped a fresh strawberry into Dennis’s mouth and we all hopped back in the car. That night the girls and I made an entire meal with the produce and other discarded food. Then we presented Dennis with his cake.

Such joy.

Things took a turn late in the summer when Wilson suggested Manson come to his studio to record some of his music.

At first, Manson was excited. But he did not like Wilson’s team or producers trying to mess with his music, which is what apparently happened. Manson pulled a knife. It went downhill from there.

The “family” wound up moving out. Though Manson and Wilson would occasionally still see each other, their relationship all but ended by summer’s end, Lake wrote, over music.

In September 1968, the Beach Boys recorded a version of Manson’s “Cease to Exist,” changing some of the lyrics and renaming it “Never Learn Not to Love.” The song, credited to Dennis Wilson as the only writer, later found its way onto a Beach Boys album.

Not long after, Wilson found a bullet on his bed.

“I gave him a bullet,” Manson later said, “because he changed the words to my song.”

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