THERE’S a scene from Jonah Hill’s new movie “The Sitter” that you’ll probably never see, in which things got a little too real.

It was supposed to be a comic exchange between Mr. Hill, the “Superbad” and “Get Him to the Greek” wisenheimer, and Bruce Altman, the actor playing his absentee dad who won’t help his son amid a particularly wayward night of substitute caregiving. But the scene took an unexpectedly poignant turn as Mr. Hill let loose upon an unreliable parent who had never been there for him, and who had abandoned him and his mother to start a new family.

As Mr. Hill later said of this scene, “It felt really tough and raw and honest and hard to watch in a great way.” And as he and his “Sitter” director, David Gordon Green, came to agree, it had no business being in an antic, R-rated Jonah Hill comedy.

These days no one can rightly take issue with the acting chops of Mr. Hill, who at 27 has arguably found the role of a lifetime in Bennett Miller’s adaptation of “Moneyball,” playing Peter Brand, a schlubby, soft-spoken whiz kid who helps Brad Pitt’s Billy Beane reinvent the Oakland Athletics by recognizing the value of underappreciated talent.