Light it up.

Paul McCartney is looking back on a very fond memory he has of the time legendary singer Bob Dylan introduced The Beatles to some very powerful grass.

In an excerpt of his upcoming memoir — “The Lyrics: 1956 to the Present” — published in the Times of London on Sunday, McCartney, 79, revealed that Dylan, 80, gave the British rock group weed during a trip to New York in 1964.

“​​What happened is that we were in a hotel suite, maybe in New York around the summer of 1964, and Bob Dylan turned up with his roadie. He’d just released ‘Another Side of Bob Dylan,'” McCartney wrote in his book. “We were just drinking, as usual, having a little party. We’d ordered drinks from room service — scotch and Coke and French wine were our thing back then — and Bob had disappeared into a back room.” 

He added that Beatles member Ringo Starr left the room and returned to the hotel “looking a bit strange.” McCartney continued: “He said, ‘I’ve just been with Bob, and he’s got some pot,’ or whatever you called it then.

“And we said, ‘Oh, what’s it like?’ and he said, ‘Well, the ceiling is kind of moving; it’s sort of coming down.’ And that was enough. After Ringo said that, the other three of us all leapt into the back room where Dylan was, and he gave us a puff on the joint.”

McCartney continued to say that the band kept smoking after their first hit because they thought that they didn’t feel any high from it.

He recalled, “Suddenly it was working. And we were giggling, laughing at each other. I remember George trying to get away, and I was sort of running after him. It was hilarious, like a cartoon chase. We thought, ‘Wow, this is pretty amazing, this stuff.’ And so it became part of our repertoire from then on.”

McCartney has been an avid pot smoker over the decades. However, in a 2015 interview with the Mirror, the musician said he stopped getting high after becoming a grandfather. He has eight grandchildren from his daughters Mary and Stella.

“I don’t do it anymore. Why? The truth is I don’t really want to set an example to my kids and grandkids. It’s now a parent thing,” he said at the time. “Back then I was just some guy around London having a ball, and the kids were little so I’d just try and keep it out of their faces.”