Even the toughest documentarians can cry.

Last April at a Boston hotel while talking about his new film, “Tony Robbins: I Am Not Your Guru,’’ a record of Robbins’s six-day Date With Destiny seminar, Joe Berlinger described himself as “not a crier.’’

Yet in 2012, when it seemed as if he had everything he wanted from life — success at a dream job, awards, respect from peers and the audience, a great wife and kids — he was not happy.

His partner, Bruce Sinofsky, with whom he made the relentless “Paradise Lost’’ trilogy (1996-2011), which gained freedom for three men wrongly convicted of murder, had died that year after a long illness. No doubt that was part of Berlinger’s malaise. But there was something deeper.

A chance meeting with Robbins, the popular business adviser and life coach, led to Berlinger’s participation in a Date With Destiny seminar in Boca Raton, Fla.

On the second day, to Berlinger’s surprise, the tears began to fall.

Q. Had you known anything about Tony Robbins before this first meeting?

A. I didn’t even know he did seminars. I thought it was just the DVDs. The self-help tape guy with a cameo in [the 2001 Farrelly Brothers comedy] “Shallow Hal.’’ I think he sensed I had some issues going on or he was just being nice or whatever, but he invited me to the next Date With Destiny, in Palm Springs.

At the first break on the first day, I didn’t walk, I ran to the exit. All my red flags went up — the hugs, the dancing, pairing off with someone to share your intimate feelings. I called my wife and she convinced me to stay a second day.

Q. And that’s when it happened?

A. Yeah. On the second day is that childhood-regression exercise which actually takes 40 minutes, in a dark room. . . . And I have some childhood issues that I was dealing with. It’s not like I’m devoid of emotion, but I can’t remember the last time, other than in 2012, in which I’ve had a deep guttural cry. Something lifted. I thought, maybe there’s something to this.

Q. “Your fans usually expect you to uncover something that undermines your subject, revealing the ugly truth. But it never happens in this film. How do you think that plays out?

A. I’ve made a lot of feel-bad movies. Films that shine a light on injustice, like the polluting corporations, in “Crude’’ [2009], and the corruption in the FBI and the Department of Justice, in “Whitey’’ [2014]. This time I had a positive experience. I wanted to share it cinematically with other people.

Q. Do you think this experience will influence your future filmmaking?

A. Well, I’m doing a film on genocide next. So I guess I’m back to my old thing.

“Tony Robbins: I Am Not Your Guru’’ is available on Netflix beginning on July 15. www.netflix.com/title/ 80102204

Interview was condensed and edited.petervkeough@ gmail.com