Everything impressive and overstated and bombastic and affecting about Jonah Hill’s breakthrough performance in “Superbad” (2007), dozens of movies ago, translates to the actor’s directorial feature debut, the semi-autobiographical slice of life “Mid90s.”

Hill also wrote this technically accomplished, sporadically heartbreaking portrait of a rough, risk-prone adolescence. I found it far tougher to watch, at its harshest, than just about any recent movie about a kid adrift in what Hill calls the “animal kingdom.” It owes a debt to Larry Clark’s “Kids,” unfortunately, as well as several really good coming-of-age chronicles. It’s more nerve-wracking than “Eighth Grade,” by a factor of several hundred. It’s a tougher sit than “Hereditary,” in fact.

Its first shot fixes the action inside a small house somewhere in LA in the 1990s. We’re looking at an empty hallway. Two boys, brothers, tumble into view, hit the wall and the crunch of the younger one’s face against drywall is deafening.

(Hill cranks the sound at all the obvious moments throughout.)

This is Stevie (played by Sunny Suljic), and his mean, unhappy older brother, Ian (Lucas Hedges). Their mother, Dabney (Katherine Waterston), doesn’t seem to intervene in much of anything, until Stevie starts hanging around with his new tribe, a group of skateboarders including a perpetually videotaping kid named Fourth Grade (Ryder McLaughlin); Ruben (Gio Galicia), Stevie’s surly, insecure mentor; the one with the unprintable moniker combining two world-­famous swear words (Olan Prenatt); and the older, wiser, kinder Ray (Na-Kel Smith), Stevie’s friend and protector in the later scenes of “Mid90s.”

Fleeing from an abusive sibling, Stevie explores this wondrous, intimidating world of the slightly older, cooler, rougher kids outside his house. Stevie learns to smoke, and drink, and get high, and skate, a little. He learns never to say thank you because, as Ruben snarls, it makes him sound “gay.”

Shot with sleek, vaguely falsifying assurance by cinematographer Christopher Blauvelt, the film darts from home to skate shop, from skate park to skate park, from brawl to car crash, while the soundtrack lays in the GZA rap and ambient, don’t-­worry-it-gets-worse dread from composers Trent Reznor and Atticus Ross. Hill attracted a classy group of collaborators, and his on-screen talent, mostly amateur, works well in the context of the movie. Much of the dialogue feels improvised, sometimes effectively; all of it, however, presents Stevie as a generic, rather than specific, bundle of heartfelt good intentions and spongelike adaptability.

Eleven at the time of filming, Suljic handles everything from a dicey sexual initiation scene (Alexa Demie plays the barely characterized older girl drawn to the sensitive newbie) to an arresting, abbreviated emotional blowout with Waterston. This crucial scene’s over before it starts, frustratingly. Vivid in bits and pieces, “Mid90s” feels like a research scrapbook for a movie, not a movie. The more Hill throws you around in the name of creating a harsh, immediate impression, the more the impressions blur.

Hill will make far better pictures: As an actor, it took him a few films after “Superbad” to discover the payoff in doing less, and less obviously. The director in him may need another project to figure that out, whatever story he tells next.

“MID90S”

**

(R, 1:24)