Jay Bulger discusses his new doc about Cream’s Ginger Baker

Jay Bulger deliberated about how much of a part he should play in “Beware of Mr. Baker.” The writer and director’s debut documentary focuses on the impulsive and explosive life of drummer Ginger Baker, who is best known as the thunderous beat behind Cream, the 1960s band that defined the term “supergroup.” It might at first seem superfluous to include the personal story of the filmmaker, especially because Baker is such a one-of-a-kind character whose history is dense with so much unabashed sex, drugs, rock ‘n’ roll and violence. But some of those forces inevitably leaked into Bulger’s own life while making the film.

“I was like, ‘God, I’m there so much and you hear my voice, I should probably show who I am,’” says the filmmaker. “And then when he broke my nose with a cane, I thought that was such an indicative moment of who he is and how he deals with people.”

The assault begins and ends the doc, but between these personal bookends, Baker tells of a troubled childhood and how he escaped through an enchantment with rhythm and, soon after, heroin. Both are constants during his meteoric rise to fame and many falls from such dizzying heights.

Lounging in a leather chair in his South African home, Baker often berates Bulger.

“It’s like boxing,” says Bulger. “Sometimes you’ve got to take a couple punches before you can get inside.”

And he does get inside. The drummer opens up about the bridges he has burned between family and friends. Then Bulger interviews those same people, including bandmates Eric Clapton, Jack Bruce and Steve Winwood. That Bulger would do this is why Baker hits him.

“I loved the challenge of doing a movie about somebody who is so potentially unlikable,” says the filmmaker.

But what really gives “Beware” its driving beat is the vintage footage of its subject, wild-eyed and wild-haired, gangly limbs flailing all over his drum kit throughout the decades and basically looking like a person who is destined to die young.

“As much as you want to hate him, you’ve got to love him because he still keeps going,” says Bulger, “and he never compromises.”

How did Baker react when he saw the film?

“He was like, ‘I loved the first half — the second half, not so much,’” laughs Bulger. “I was like, ‘Oh yeah, you mean the half where your life goes to s— and you keep making mistakes, ruining opportunities and squandering for-tunes?’ … If that’s his res-ponse, where it could have been, ‘I’m gonna f—ing kill you,’ I think that’s a success.”