Every Christmas Eve, three childhood friends have honored their tradition of gallivanting and imbibing across New York City, a ritual that first began when a tragedy united them a decade earlier. After Ethan's parents were killed in a drunk-driving accident, Isaac (Seth Rogen) and Chris (Anthony Mackie) vowed to forgo their familial obligations and spend the holiday night together every year. Now entering their thirties, the trio have decided that this year's blowout will be their last go-round -- Isaac and his wife Betsy (Jillian Bell) are expecting their first child, and Chris, a professional football player, is experiencing a career resurgence that has led to a massive spike in his celebrity. Ethan (Joseph Gordon-Levitt) is the only one whose life is still stuck in neutral; he's a failed musician who lost Diana (Lizzy Caplan), the love of his life, due to a fear of commitment. However, his lowly job as a cocktail waiter gives him the opportunity to steal three tickets to the Nutcracka Ball, the most exclusive Christmas Eve bash in the city, from a snooty patron. Since Ethan, Isaac, and Chris have been searching for a way to get into the elusive party since the very beginning of their tradition, this year's night of wickedness promises to be an especially unforgettable one. In addition, Betsy has bought Isaac a box full of drugs for the boys' night out (and he immediately eats the mushrooms she procured from Craigslist), while Chris desperately wants to show up to the Ball with a sack of weed for his football cronies. Thus, the trio contact their weed dealer from their high-school days, Mr. Green (a wonderfully out-of-character Michael Shannon). The peculiar, prescient Mr. Green has separate interactions with each of the men during a drug-fueled glimpse of their past, present, and future Christmases. Later, the gang's hazy trip to the Ball includes some Run-D.M.C. karaoke, a chance meetup with Diana, and a dick-pic cell-phone mishap. Some gags are huge misfires, but there are enough laughs here to keep the stoners' adventures afloat. The Night Before is also stacked with a litany of celebrity cameos, yet the results are a mixed bag. There are genuinely funny appearances early in the film by Nathan Fielder as a campy limo driver and Broad City's Ilana Glazer as a kleptomaniac holiday grinch, but the story gets bogged down by the arrival of Miley Cyrus and James Franco (the latter at his insufferable worst) toward the conclusion. While his racy, drug-heavy brand of comedy might not be for everyone, Seth Rogen has proven time after time that he can carry a movie. That being said, he's largely wasted in The Night Before as his character is reduced to a film-long psychedelic trip. The bit grows tiresome before even the first third is through, and it prohibits Rogen from really reaching out and taking control of the flick. Chris' self-obsession and lust for fame make him a flimsy character, although at least the seasoned Mackie has plenty of charisma to skate by on. That leaves the heavy lifting to Gordon-Levitt's Ethan, who is the only character here with any compelling depth. Ethan has never properly dealt with the loss of his parents a decade earlier, which is the impetus behind his clinging to the trio's Christmas tradition. Unfortunately, this potentially intriguing idea goes largely undeveloped, save for one touching flashback to the inaugural night when the gang first hatched their ritual of debauchery. Those misgivings aside, The Night Before is comfortable existing in the grey area of holiday fare between the crude and the overly sappy. The script (co-written by director Jonathan Levine, Kyle Hunter, Ariel Shaffir, and Evan Goldberg) is effective enough at finding a balance between those two extremes to make the movie worth revisiting at Christmastimes to come. After the kids are safely tucked in bed, of course.