He has previously described the same encounter, as a 12-year-old boy, in the ranch used for films and TV shows where owner George Spahn allowed Manson and his murderous acolytes to live in.
In an interview with the Daily Beast last year, Cranston recalled riding with his cousin and hearing a man in his 20s yelling "Charlie's on the hill!".
"Everybody looked around, and there was this frantic nervous energy going on, and they all jumped on horses and away they went," Cranston told the Daily Beast last year. "We asked the old guy [Spahn] what was going on, and he said, 'Oh, it's nothing. It's happened before.' We thought, 'Well, Charlie must be someone important'."
Curious as children often are, Cranston and his cousin rode to find "Charlie" to see what the fuss was all about. They found Manson high on drugs.
"There were about eight or so people, and there was a man in the middle on a horse, but he wasn't holding his own reins - there was someone on the horse in front holding the reins - and Charlie, I guessed, was this comatose, bearded, long-haired guy with big eyes riding as if he's just stuck to the back of a horse. Totally zoned out. You couldn't take your eyes off him," he said.
"My cousin turned back to me and said, 'Wow, that guy's weird'. When we passed him and their whole group, she turned around again and said, 'That must be Charlie', and I said, 'Yeah ... and Charlie's freaky!' We didn't think anything of it."
When news of the murders broke the following year, Cranston and his cousin immediately recognised "Charlie" on TV.
"I saw his face on the news, and my jaw dropped," Cranston said. "My cousin called me first and said, 'Can you believe this?' The picture of Charlie Manson was the guy on the back of this horse. And we thought for a second, 'Oh my god, what if?' It was very freaky, to say the least. Oh, man."