There are conversationalists, there are kitchen philosophers, and then there is Kenny Shopsin.

For more than three decades, the gray-haired, pot-bellied Shopsin has presided over the grill of the compact Greenwich Village restaurant that bears his name. Everybody has to play by his rules, from the customers to his wife, five children and one employee.

Not a regular? Who needs ya. Party of five? Fuhgetaboutit.

In a world of chain stores and gentrification, Shopsin is an endangered species. In an era of “Have a nice day” and “Would you like fries with that?,” Shopsin’s motto might be, “My way or the highway.” With the f-word sprinkled in.

Shopsin isn’t abrasive so much as unvarnished. He works incredibly hard, and his reward (aside from supporting his family) is that he’s king of his domain. He sets the policy, he controls his environment and he’s got it pretty well laid out after all these years.

The altogether wonderful documentary “I Like Killing Flies” is an affectionate yet unadorned picture of Shopsin on the job — that is, at the center of his universe. A bracing record of individuality, idiosyncrasy and iconoclasm, the film is as refreshing as a dip in the Atlantic Ocean.

“I Like Killing Flies,” which screened in the 2004 San Francisco Jewish Film Festival, opens Friday, Oct. 20 at the Roxie Film Center.

Shopsin faces everything head on — he’s a working-class New York Jew, after all — including the loss of his lease. As wrenching as it is to leave his comfort zone, he doesn’t hesitate to take on with his family the mammoth task of moving everything to a new location several blocks away.

The original intent of the film, supposedly, was to document the original location and Shopsin’s move. Fortunately, it also captures the force of nature that is Shopsin, and his wit, wisdom and warmth.

Take the menu, which lists more than 900 items, all made from scratch. Many derived from mistakes, happy accidents or perverse experimentation, needless to say.

“That’s the basis of all fusion cooking, that there’s a sexual friction that’s caused by putting the wrong ingredient in the wrong place.” Shopsin pauses and smiles. “Sometimes it works,” he says. “Not always.”

That sequence may offer the best insight into his character. He’s that rare bird who acts on impulse, lives without regrets and keeps moving forward.

In fact, it’s apparent early on that Shopsin isn’t doing shtick or exaggerating his persona for the camera. He’s neither stupid nor unreflective, but he rarely bothers to filter before he speaks.

His wife and children, necessarily, have learned to adjust to him. As you might imagine, they’re all tough cookies in their own right.

At its core, “I Like Killing Flies” is a movie about work and family. Its depiction of sacrifice and teamwork, authority and pride, is crammed with hard truths.

Shopsin’s relocation highlights the tug of war between stability and change (growth would be too grandiose a word). It’s plain to see that the emotional upheaval of moving to the larger, airier site is on par with the financial risk.

But if Shopsin is a creature of habit, he is also a survivor capable of adjusting to almost anything. Ultimately, his restaurant is more than the way he makes his living — it is his purpose in life.

Such deep insights notwithstanding, Matt Mahurin’s documentary is as unpretentious as its subject. That erases any whiff of pompousness from Shopsin’s pronouncements, even when they’re as profound as this nugget:

“The big demarcation point, I think, in human behavior — if you treat people with respect who don’t deserve it, it’s a mark of high civilization.”

“I Like Killing Flies” plays Oct. 20-26 at the Roxie Film Center at New College, 3117 16th St. (at Valencia), S.F. Tickets: $4-$8; www.roxie.com or (415) 863-1087.