In his new book, Man on the Run: Paul McCartney in the 1970s, music journalist Tom Doyle gives fans some long-desired insight into McCartney’s life after leaving the Beatles.

Through exclusive interviews with McCartney and the still-living members of the musician’s inner circle during the dark decade, Doyle learned how much of a struggle the ’70s were for McCartney.

“He knew he was in trouble the morning he couldn’t lift his head off the pillow. He awoke facedown, his skull feeling like a useless dead weight. A dark thought flashed through his mind; if he couldn’t make the effort to pull himself up, he’d suffocate right there and then,” writes Doyle in the book. “Somehow, as if it was the hardest thing he’d ever done, he summoned the energy to move. He flipped over onto his back and thought, Jesus… that was a bit near.”

After John Lennon announced his desire to leave the Beatles on Sept. 20, 1969, McCartney began to feel “utterly worthless” and fell into a deep depression. Only his wife Linda was able to save him from his substance-induced stupor.

“His often sleepless nights were spent shaking with anxiety, while his days, which he was finding it harder and harder to make it through, were characterized by heavy drinking and self-sedation with marijuana. When he did get out of bed, he’d reach straight for the whisky, his drinking creeping earlier and earlier into the day. By 3 in the afternoon, he was usually out of it.”

Linda helped him start writing songs again, and soon he began secretly recording inside of a makeshift studio on his farm. McCartney then saw minor success with his new band Wings, but the band faded away after the singer was arrested on Jan. 16, 1980 for alleged possession of marijuana. He had already been busted for public doping in Sweden and Scotland, but he proceeded to try to bring a half-pound of marijuana into Japan anyway.

“If any word sums up McCartney in the 1970s, it is struggle. Another is escape. He spent the decade struggling to escape the shadow of The Beatles, effectively becoming an outlaw hippie millionaire. It was a time of brilliant, banned and sometimes baffling records,” writes Doyle. “For McCartney, it was an edgy, liberating, sometimes frightening period of his life that has largely been forgotten by those who were not along for the ride.”