When in doubt, open with a joke. That’s the route taken by Ferne Pearlstein’s The Last Laugh, which breaks the ice with a good-natured gag about the most amenable of subjects: Adolf Hitler. This particular quip, delivered in stereo by talking heads of Gilbert Gottfried and Rob Reiner, is hardly one of the more scandalizing of the documentary’s many–it involves two Jews staking out the führer’s house on a mission to assassinate him–but is also not the sort of yarn you’d spin in unfamiliar company. Other gags recited over the course of the feature veer edgier, but still make a case for their propriety when afforded the right time and place; others still test these bounds across the board, prompting critics to insist that such a devastating notion can never give way to comedy. So who’s right?

The Last Laugh spends its time hacking through the thick of that unnavigable grey haze, examining qualifiers like context and intent to determine if the indomitably tragic subject matter of the Holocaust can and should ever be joked about. The film enlists some of the world’s leading authorities in Jewish comedy, and on comedy in general, who fill out the wide margins of the discussion. We hear from comic icons like Mel Brooks and Carl Reiner and contemporary provocateurs like Sarah Silverman and Jeffrey Ross, as well as The Simpsons‘ Harry Shearer and Seinfeld and Borat director Larry Charles, among a slew of others. All weigh in on questions of “too far,” each contributing a vantage point decidedly distinct from the last.

But perhaps the most intriguing perspective the movie spotlights is that of Renee Firestone, herself a Holocaust survivor whom The Last Laugh visits at home, accompanies to meet and relate with fellow survivors, and follows her back to the remains of the concentration camp that once imprisoned her. Though tethered personally to the tragedy in a way that the showcased comic minds aren’t, even Firestone is not without her own ethereal grey areas. No, she won’t laugh at Sarah Silverman’s shocking stand-up, but she will encourage her peers to trade in the dark shadows of the past for the joys of today.

The Last Laugh could conceivably stand to get even deeper (and darker) in its analysis, perhaps casting too wide a net to really dig to the core of any of its discussions. Still, comedy scholars and novices alike should delight in the exhumation of topics like Jerry Lewis’ never released film The Day the Clown Cried and the unaired Seinfeld episode about Elaine purchasing a gun. We hear polar opposite takes on the merits of Life is Beautiful and the shocking one-liners of the late Joan Rivers. And we get to watch Mel Brooks do a bit about Nazis mangling up his face with a roll of scotch tape. Tasteless? Funny? Somewhere in between? The Last Laugh lets you decide.

Rating: 4 out of 5

Images: The Film Collaborative/Journeyman Pictures, Comedy Central