You know how hilarious it can be to watch grown-ass adults behave like children? Well, ‘Adult Beginners’ is another one of those movies. Thankfully, it’s also a pretty good one.

Nick Kroll stars as a would-be entertainer whose Google-Glass-like product fails spectacularly at its launch party in the first scene, which essentially ruins his life and leaves him homeless. Desperate, depressed and destitute (the three big Ds of comedy), he begs his sister to let him live in her house for a few months until he get back on his feet. She (Rose Byrne) isn’t thrilled about the idea, but her husband (Bobby Cannavale) is all for it. So, Kroll sleeps on an inflatable mattress in his old childhood home and spends his days working as a nanny for his 3-year-old nephew. It’s hard at first, but soon good old-fashioned family bonding begins and Kroll starts to learn that his seemingly together sister and brother-in-law are just as lost and lonely as he is. Heck, maybe we all are. Yep, it’s one of those movies.

‘Adult Beginners’ is the directorial debut of Ross Katz, who previously served producing duties on films like ‘In the Bedroom’ and ‘Lost in Translation’. Katz knows how to make a weepie with laughs, but also knows not to aim too high in his directorial debut. So he shoots for a disarmingly sweet tone with moments of bitter comedy. His film might hit all of the beats expected from a Sundance-friendly indie dramedy, but at least he hits them well and has cast his flick perfectly. Kroll delivers a surprisingly pained and nuanced performance for a guy who previously specialized in surreal comedy characterizations. He’s still funny, but shows off a side of his talents that few could have predicted. It’s a role that should kick open a new chapter in his career.

Yet as good as Kroll is, Byrne is even better. She’d never really done comedy until recently, but has proven to have a such natural comedic charisma to match her acting chops that she should stay in the genre for a quite some time. Bobby Cannavale essentially reprises his role from ‘Blue Jasmine’, but he’s so good at it that it’s hard to care, while ringers like Joel McHale and Bobby Moynihan pop up to score big laughs when the tone gets too heavy.

‘Adult Beginners’ is a very modest human comedy that sets its bar fairly low and succeeds kind of beautifully on its own terms. It’s a whisp of a dramedy, a movie that shoots for nothing more than warmhearted cuteness and nails it.