The fifth episode of Justin Bieber: Seasons, his 10-part YouTube docuseries, explores his troubled past.

The latest episode, “The Dark Season,” now available on YouTube, finds the “Yummy” singer reflecting on his inner demons and addiction, unlike the first four, which focused on his new album and romance with Hailey Baldwin.

“It feels good to share, to be honest,” he says in this chapter. “I wasn’t ready or mature enough to take responsibility and mean it.”

In an Instagram update before the docuseries’ YouTube debut, Bieber wrote, “While a lot of people kept saying Justin Bieber looks like s—, on meth etc. they failed to realize I’ve been recently diagnosed with Lyme disease, not only that but had a serious case of chronic mono which affected my, skin, brain function, energy, and overall health.”

Episode 5 begins with a trigger warning that “contains raw and honest discussions about addiction and anxiety.” The actor later admits to smoking pot for the first time aged 13, saying he was “really dependent on it.”

Bieber then says he started drinking lean (also called “purple drank” or “sizzurp”), taking pills, and trying other drugs as a “escape.”

His wife, 23, says, “I think when you take somebody very, very young and they start to get horrible, crazy, crippling anxiety and it goes undiagnosed and you don’t know what it is that you’re feeling. Self-medicating helps you feel better and not feel anything.”

Scooter Braun, Bieber’s longtime manager and buddy, says his “dark period” began at 19.

“I started valuing the wrong things in this business because there were things dangling front of me,” Bieber says.

How he stopped is then explained. “I was dying,” he claims, explaining that his security crew checked his pulse at night to ensure his survival.

“People don’t know how serious it got,” he says. “It was insanely scary.”

Bieber says, “So many people have gifts or opportunities to change. Their gifts are lost or used selfishly. It seems like so many talented individuals waste something precious. As individuals, we must use our gifts to contribute.”

To eliminate his toxins, he gets nicotinamide adenine dinucleotide IV at the doctor in the newest episode.

“I’ve abused my body in the past and now I’m just in the recovery process, trying to take care of my body and the vessel God gave me,” he adds.

Bieber’s docuseries debuted late last month and will air through February, once his fifth studio album is released. Changes is his first album since 2015’s Purpose and will be released on Feb. 14.

YouTube has the first five Justin Bieber: Seasons episodes.