Starring Ben Stiller and Naomi Watts. Rated 14A.

When Albert Maysles died recently, there went one leg of an aged tripod of fly-on-the-wall filmmakers whose work defined what we think of today as serious documentaries. (Remarkably, Frederick Wiseman, 85, and D.A. Pennebaker, 89, are still at it.) They were models for Paul Reiser’s character on Mad About You, and many of his kvetchy concerns and relationship dynamics inform Ben Stiller’s uptight filmmaker in While We’re Young, Noah Baumbach’s best and most painfully insightful effort since his 2005 breakthrough, The Squid and the Whale.

When we meet him, Stiller’s Josh has been working for 10 years on one project, vaguely built around a Chomsky-like philosopher (played by Peter Yarrow, of Peter, Paul and Mary). Josh’s Helen Hunt–blond wife, Cornelia (Naomi Watts), is starting to lose faith in him, especially since he has so manifestly failed to achieve the stature of her father (the great Charles Grodin), a Wiseman-like doc legend. And the childless New Yorkers are feeling unwanted family pressure from early-40s friends, such as the new parents well played by Maria Dizzia and Beastie Boy Adam Horovitz.

Josh and Cornelia’s trajectory changes when they meet a younger couple who admire them. Jamie (Girls star Adam Driver) is himself a would-be filmmaker and Darby (Amanda Seyfried) makes artisanal ice cream in strange flavours. Young’s central riff, initially, has the middle-agers hooked on their up-to-date gadgets while the hipstersomethings wear thrift-store hats, collect old vinyl, and watch The Howling on VHS.

The older couple is charged by this connection, exploring old subway tunnels and taking ayahuasca on the weekend. But when they start working together on Jamie’s first doc, suspicions grow that the earnest youngsters might have more killer instinct than they first let on. Things culminate in a cleverly structured verbal explosion that perhaps draws too much attention to Baumbach’s writerly concerns. And the female characters take a back seat here, which wasn’t true for Frances Ha or his other recent movies. But this briskly paced flick’s pitch-perfect view of moral shifts in the information age is as funny as it is frightening. And, well, it just feels real.