Beach Boys' Mike Love recalls meeting Charles Manson through bandmate Dennis Wilson

It was 1968 when Beach Boys lead singer and co-founder Mike Love met Charles Manson, who he says was "the worst thing that could possibly happen" to the band.

"You know, it's just an unfortunate episode that happened because of one of our group members, one of our family members unknowingly invited Satan into our midst," Love, 75, told ABC News.

Manson was a cult leader who incited the Aug. 9, 1969, murder of actress Sharon Tate and four others. Tate was stabbed to death at her Benedict Canyon, California, home by Manson's followers, along with her friends Jay Sebring, Wojciech Frykowski and Abigail Folger, and Steven Parent, who had been visiting the property's caretaker. Manson also led his followers to murder Leno LaBianca, who ran a successful grocery business, and his wife Rosemary LaBianca on Aug. 10, 1969.

Love said Dennis Wilson, his cousin and the drummer for the Beach Boys, introduced him to Manson a year before the gruesome killings. Love wants people to understand that it was only Wilson who befriended Manson and that this was before Manson and his followers committed murder.

"Dennis was enthralled by him at one time, and it didn't hurt that Charlie Manson came with this group of girls -- young girls, who were very enamored with Charlie, and looked up to him as a leader," said Love.

Wilson told Love he met the cult leader after he picked up two young women hitchhiking who turned out to be followers of Manson.

"They actually invited themselves in after Dennis picked up a couple of the girls hitchhiking on Sunset Boulevard and took them back to his home," Love said. Wilson left, and when he later came back home, according to Love, Charles Manson and the girls were living in his house.

Love said Wilson would continually tell him and the other Beach Boys members about Manson, calling him "the wizard" and saying that he wanted them to become Manson family members.

"He wanted us to join the group," Love said of his cousin.

One evening when the band was recording at co-founder Brian Wilson's Bel Air, California, home, Love said Wilson invited him and band member Bruce Johnson to dinner at his house to meet Manson and the family.

At the dinner, Love said there were several women, and Tex Watson, who participated in the Tate and LaBianca murders.

"Bruce Johnson and I were the only people at dinner who had clothing on. Everybody else was completely naked. So first of all, that's a little weird," Love said. "Right after dinner, Charlie invited everybody to go in a den area, and turn on a strobe light, and passed out what was said to be acid, which I declined. I wasn't interested in doing that, nor was I interested in joining the bodies that were, you know, on the floor."

Love said he excused himself because he was happily married at the time and didn't want to participate.

He said it was a hot summer night, so he went to Wilson's bathroom to take a shower.

Shortly after, Love said, Manson opened the shower door and confronted Love.

"He said, 'You can't do that.' I said, 'Excuse me.' He said, 'You can't leave the group,'" Love said. "It was a pretty intense look. And so I said, 'Oh, I'm sorry Charlie, but I just -- we've got to get going back to the studio.'"

Love said he and Johnson left as quickly as they could and returned to Brian Wilson's house.

"I can remember driving back to Brian's house, just a couple miles down Sunset Boulevard, thinking, 'Well Dennis, you really got 'em. You really got something on your hands now,' you know?" Love said.

Dennis Wilson went on to spend more time with Manson and his followers. According to Love, Wilson paid over $1,000 for penicillin shots to treat gonorrhea Manson and his followers had passed on to each other.

"He paid for a lot of things like food and transportation and medication. But, you know, I heard all this subsequent to that invitation to dinner," Love said. "I never knew that [Manson] was this outright murderous person ... I just knew that he was really intense and really had a spellbinding effect on these young ladies."

Wilson also tried to engage the Beach Boys in helping Manson musically, Love said.

"In fact, we did one song that was essentially started by Charlie Manson and then re-crafted a bit," Love said.

The band recorded the song, "Never Learn Not to Love," which was originally titled, "Cease to Exist," and performed it on "The Mike Douglas Show" in 1969. Love said he thought Wilson wrote the song and didn't learn until much later that it was originally a song written by Manson.

"Manson was furious when he found that Dennis Wilson had not only changed the lyrics but had listed himself as the sole composer, and at one point, [Manson] leaves a bullet and tells Wilson, 'I know where you live. I know where your children are,'" said Jeff Guinn, the author of "MANSON: The Life and Times of Charles Manson."

Wilson also introduced Manson to his best friend and music producer Terry Melcher in the hopes of helping jumpstart Manson's music career. Melcher was the son of movie star and singer Doris Day and a very talented music producer with many hit records.

Melcher had the power to sign an artist to a recording contract. He produced classic '60s songs, such as the Byrds' version of Bob Dylan's "Mr. Tamborine Man," "Turn Turn Turn" and other hits.

After being pursued by Manson for months, Melcher showed some interest, according to multiple sources, and even came out to Spahn Ranch to listen to him. But eventually, he decided Manson wasn't talented enough and decided against giving him a recording contract. Manson was furious.

Melcher lived in a home he rented on Cielo Drive in Benedict Canyon, California, with his girlfriend, actress Candace Bergen. Melcher and Bergen moved out in January of 1969.

Shortly thereafter, Sharon Tate and her husband Roman Polanski moved into the home, where Manson would eventually send his followers. Manson told Tex Watson to kill everyone in the house. Manson told Susan Atkins, Linda Kasabian and Patricia Krenwinkel to do what Tex said.

Love said he and the band were completely stunned when they learned what Manson and his family had done.

"It was a huge shock. It was a huge shock to all of us that Charlie Manson had actually been recording in the studio at my cousin Brian's house, where we recorded," said Love.

He said he thinks Dennis Wilson especially feared for his life with Manson. Wilson actually moved out of his own house and left Manson and the followers there. Love says Wilson was horrified to learn that Manson and his followers committed the brutal Tate and LaBianca murders.

"For my cousin ... our group member to be involved with that and to have the guilt associated with that, I mean, had to be a tough ... burden for him to carry for the rest of his life," said Love.