During a “Weekend Update” segment of Saturday Night Live that aired in March, co-anchor and SNL co-head writer Colin Jost screwed up.

It was the best thing he had done all season.

The flub in question came near the peak of frustration over what many critics had ruled as a floundering section of “Weekend Update” history. A segment that had often been the highlight of the sketch program had, in its 40 th season , proven to be one of its most problematic .

“It’s the blessing and the curse of it,” Jost tells me of the hyper-intensive scrutiny placed on “Weekend Update” week in and week out.

This segment—not in spite of, but because of this screw up—proved to be one of the more “blessed” outings. Or at least its funniest. Jost misread the cue card for a joke about a study on men’s average flaccid penis length. “36 inches” he said, instead of the more accurate 3.6 inches.

Jost’s trademark smirk, a lightning rod that alternately endeared him to fans and aggravated the hell out of critics, melted as he giggled at himself and his goof. “A guy can dream,” he ad-libbed.

Part of the reason the candid moment—a failure that evolved into a comedic victory—resonated so much with the critics who had been so hard on Jost is that it finally revealed a human living behind that hitherto robotic smirk. And a pretty fun and (this is the important part) funny human at that.

Despite making headlines as one of the youngest Saturday Night Live writing hires ever (Jost was just 22 when he arrived at Studio 8H from the Harvard Lampoon in 2005), then being named one of the show’s head writers when Seth Meyers departed in 2012—a promotion that led to his current “Weekend Update” tenure—Jost has, unlike his more publicly charismatic predecessors Tina Fey and Meyers, been a bit of a public mystery.

In fact, his status as a comedy enigma (What makes him tick? What’s his point of view?) might be one of the most confusing and, to critics, irritating things about him.

And that’s why his latest venture, the semi-autographical feature film Staten Island Summer, is so gratifying.

Through the lens of the Superbad-meets-American Pie coming-of-age comedy that Jost wrote, Lorne Michaels produced, and half of the current SNL roster (including Cecily Strong, Bobby Moynihan, and Kate McKinnon) co-star in, we go behind the smirk and learn more about the comedy genius who earned so many Big Chances, from young hire to head writer to “Weekend Update” anchor.

(As it turns out, Colin Jost is less the wooden “Update” host he’s painted to be, and more the guy who laughs at penis size.)

More, the film proves that given the opportunity to polish his jokes and showcase his biggest comedy asset—himself—Jost may be deserving of more credit than he’s getting.

Staten Island Summer, which will have a small theatrical release this weekend before becoming available on Netflix on July 30, is both a love letter to and parody of the Staten Island neighborhood where Jost grew up, before he left the stereotypes of its squawking residents and Jaeger-addicted juiceheads to attend Harvard University.

It’s a version of Jost’s own life; his family still belongs to the Great Kills Swim Club where the film’s protagonist works as a lifeguard the summer before moving to Cambridge. And, in the One Last Rager Before We All Part Ways teen-movie tradition, it’s the perfect balance of sweet and funny, cartoonish and also extremely relatable.

“There’s a lot about Staten Island, which I hope you see in the movie, that’s pretty idyllic,” Jost tells me. “For a kid, it’s kind of the perfect place to grow up. It’s only when I got older, in a lot of ways, that I realized people had sort of different conceptions about Staten Island.”

There’s a line in the film that Cecily Strong’s character says to Danny, the “Colin Jost” character played by The Good Wife star Graham Phillips. Looking around at the drunk moms, eight-packed meatheads, and wayward stoners swimming at their pool, she says, “Give it a while before you tell anyone at Harvard that you’re from Staten Island.”

In real life Jost, who attended Manhattan’s Regis High School before becoming a rising star and eventual president at the revered Harvard Lampoon , acknowledges that the general Harvard population generally raised an eyebrow when they found out where he hailed from. But his unusual upbringing in a locale so storied and, as Staten Island Summer proves, so ripe for parody, was worn as a badge of honor. Usually.

“When you feel like you’re struggling to get ahead in the world I think you also feel like you’re struggling to get out of wherever you grew up,” he says, echoing what is undoubtedly a universal feeling for any teenager, from Staten Island or otherwise.

“Initially I think I was eager to get off Staten Island and go away for school, that kind of thing,” he continues. “Then what you do maybe 10 years after that, you start maybe appreciating all the great things about the place you grew up. You can go back and enjoy it because you don’t have that angst or sense of struggle to get away anymore.”

Of course, outsized success helps in tempering angst.

The Lampoon-to-SNL path is an oft-charted one for Harvard alums, but rarely is it traversed as quickly as Jost took it. He had worked just six months after college writing for an animated series called Kappa Mikey when he sent a sketch packet to SNL for consideration. Soon, he met with then-head writer Tina Fey and, later, Lorne Michaels. Then, at 22, he was hired to write for SNL.

He’s been writing for the show for 10 years now, yet because of his recent promotion to head writer and his first forays on-camera with “Weekend Update,” he’s often viewed as a “fresh-faced” talent in the eyes of many comedy fans.

“People are just starting to barely discover who I am in some way,” he says. “When I started at SNL I was lucky to start early. So now starting on ‘Update,’ I am the age when most people are when they start doing that. It feels like a different world and capacity, like starting over in another challenge.” Then he adds, “A heightened challenge.”

When Seth Meyers abdicated his “Update” chair in 2014, Jost continued the tradition of head writers taking the position and joined cast member Cecily Strong as co-anchor. They shot barely a half-season together before it became clear that the “Weekend Update” magic—that Fey/Fallon, Fey/Poehler, Poehler/Meyers abracadabra—wasn’t there.

The next season, Strong was sent back to do her character work, which she had always done best, and Jost was kept on, with Lorne Michaels perhaps believing that he, with his handsome wily edge and his smirk-punctuated punchlines, could be a worthy heir to Meyers. Fellow staff writer Michael Che, the show’s first black “Update” anchor , was brought on as his comedy partner.

“It was kind of a crazy time,” Jost says, recalling the transition from Strong to Che. “Having a year now under our belt, I just feel like we know more and more what we want to do.”

For many critics, Jost’s smarm and Che’s startlingly laconic nature mixed like comedic oil and water. And for Jost, that meant two consecutive years hosting a “Weekend Update” that wasn’t quite working. Most “Update” hosts get a year grace period before finding their groove. Jost has had to find his comedic footing twice.

That’s why moments like the off-the-cuff penis snafu are so important. They indicate a comfort and, finally, an ease at the “Update” desk, signaling that the Staten Island native, so often criticized for being stiff, might be finally loosening up. That’s a good thing, as Jost confirms to me that at this juncture, the plan is for him and Che to return to the “Update” desk together next season. (“That’s my understanding, yes.”)

“We’re itching to get back and keep trying to improve,” he says. “That’s why I’m really excited about this year. Last year in the summer I was really nervous. I didn’t know if I had a job. Now I’m more anxious on a week-to-week level. I just want to get better.”

“Get better” is a bit of refrain in our “Weekend Update” conversation.

Jost, to his credit, is no fool. He knows the transition with Che has been rocky at times. After all, not only has he spent 10 years watching others host the segment, he does have social media. “I’m never content, however we’re doing,” he says. “I feel like there’s still several more gears that we have to find.”

As for the criticism? “You know, that comes with the job,” he says. “In no way can I complain if someone has a mean thing to say. That’s the job. You’re in the public eye and that’s part of it.”

But now that he’s got votes of confidence from investors backing his first feature film—including SNL producer Lorne Michaels—and a decade of writing for SNL under his belt, he’s wiser with how he deals with the criticism.

“I think when I started there were times that were very painful, just because it feels very personal,” he says. “And then over time there’s a good combination of things, where things have improved. And also now I have a thicker skin because you get knocked down and you kind of just have to keep battling through it.”

He pauses, and then speaks both to SNL and Staten Island Summer. “Then you care less about what people think and more about the work you’re doing and how you’re doing it,” he says. “I’m having fun doing it in addition to it being work.”

Finally, thanks to a 36-inch penis, we saw a bit of that fun late last season on SNL. We see it in spades in Staten Island Summer. And, as Jost pledges, we’ll see loads more of it in Season 41.