"You want to get nuts?adventures in auto-eroticism': economies of traveling masculinity in on the road and the first thir Come on! Let's get nuts." A memorable line from 1989's Batman could speak for much of Michael Keaton's filmography. Whether playing a violent vigilante defending Gotham, a poltergeistwith an ax to grind, Mr. Mom, a scheming salesman, or a series of comical clones, there's traditionally a scorching spontaneity in his performances. You don't know when he might switch from the charismatic Keaton — with the raised eyebrow and blue-collar charm — to the wild-eyed dynamo with explosive potential to be a hero or a villain. 

Having walked this line for decades on screen, Keaton perfectly casts himself in his second directorial effort, the neo-noir thriller Knox Goes Away. 

What's Knox Goes Away about?

Written by Gregory Poirier, Knox Goes Away stars Keaton as the titular anti-hero, an aging assassin whose days are numbered. However, it's not some old enemy or fresh-on-the-scene punk who's gunning for him; John Knox faces a deep betrayal from within his own body. Diagnosed with the neurodegenerative disorder Creutzfeldt-Jakob Disease, Knox has only weeks before fast-acting dementia will overtake his ability to operate independently. 

Naturally, Knox starts by getting his affairs in order; he cashes out an unusual retirement fund, updates his will, and shares the grim news with his closest friends. One is a sensitive sex worker (Joanna Kulig) with whom Knox shares Thursday afternoons and his vast collection of books. The other is Xavier (Al Pacino), an aging thief with a lust for life and a wife half his age. But Knox's exit strategy is disrupted when his estranged son Miles(James Marsden) shows up on his doorstep, covered in blood. He's killed someone, and he needs help covering it up. So, naturally, Miles turns to his killer dad. 

An expert on such matters, Knox is coolly swift in his response. But can he save his son — and maybe even their relationship — before Knox "goes away"?

Michael Keaton is the strong center of Knox Goes Away. 

This is not the fly-off-the-handle madman of '80s-era Keaton, nor is it the growling (but electrifying) old grump of Birdmanor The Flash.Leaning away from more theatrical flourishes, Keaton plays Knox as someone who's lived this long by being able to fly under the radar. Speaking softly but darkly, like a low roll of thunder, Keaton breathes backstory into this curious killer before the script does. There's no malicious glint in his eye as he goes out on assignment. There's no cocky smirk when he's cornered his mark. This is a job, pure and simple. 

Knox is a man of stern and solid expression — until he is not. Cinematographer Marshall Adams plays with overexposure and rattling POV shots to visually reflect Knox losing grip on his memories and cognition. Keaton relaxes his knit brow and dulls his hard stare, giving audiences a flash of the slippery terror of dementia. In the wrong hands, this plotline might have come off as a crass gimmick. However, Keaton plays this battle with Knox's brain with nuance, thereby inviting audiences into this savage experience and its horror. 

Keaton pulls together a crackling cast in Knox Goes Away. 

As its hero is the kind of guy who holds his cards close to his vest, this clever thriller surrounds him with more outrageous figures. Marsden, who often plays smug or humorously cocky, is well-cast here. Like Keaton, he sheds his signature swagger but instead turns in a performance blistering with fear and rage. Opposite Miles's sputters, Knox seems all the more in control — even when he's not. 

Ray McKinnon, who co-starred with Keaton in the TV mini-series Dopesick, plays foil as a fellow hit man whose aging rock-punk vibe makes him a curious companion to the philosophizing Knox. Marcia Gay Harden pops up for a powerful scene, aiming her hurt with the deadly accuracy of a pistol. Kulig is the femme fatale of this neo-noir tale, oozing sensuality as she becomes the dubious confidante of a dying hit man. Meanwhile, Suzy Nakamura (Avenue 5) brings a low-boil intensity as a police detective determined to make sense of a cavalcade of confusing clues. Her dry sense of comedy spices up exposition scenes as well as confrontations with the Knox gang. 

Keaton clearly has a sharp eye for spotting the talents of his peers, but his best pick (aside from his own casting, of course) is Pacino. Incredibly, these two stars have never appeared in a film together before. Like Keaton, Pacino has played his fair share of baddies and hard-pressed heroes. So, when he pops up in a bathtub, double-fisting Chinese takeout and a glass of wine, it's hard to guess if he'll be a friend or foe of Knox's in the end. Along the way though, it's a dizzying hoot to see Pacino playing such a gleefully sleazy eccentric. Together onscreen, there's a crisp tension and unspoken yet vibrant intimacy. But their chemistry plus their personas mean this relationship adds a fresh layer of tension, adding another question to the mix: Can this crook be trusted? 

Knox Goes Away is a lean and keen thriller. 

While the film may star its director, Knox Goes Away doesn't feel like a vanity project. Keaton gives his ensemble roles that — no matter how brief — offer a chance to shine. His own character, meanwhile, remains an enigma, sharing his overarching plan in vague snippets. As such, the script urges us to play detective, trying to uncover what exactly Knox is up to; it's an engaging activity to be sure. 

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As a director, Keaton neatly weaves together the tension of Knox's final mission with the pathos of his impending doom. There's no time to fall apart over bad luck, and Knox wouldn't dare. But instead, he opens up in small ways — not always on purpose — giving a peek to the secrets of his guarded heart. This makes for a movie that isn't just blood-pumping and mind-bending, but also gut-wrenching. You might figure out where it's going before it arrives, but you'll likely enjoy the twisted journey. 

In the end, Knox Goes Away is a must-see for Keaton fans and a solid watch for anyone in search of a thriller worth its runtime. 

Knox Goes Awayopens in theaters March 15.

UPDATE: Mar. 14, 2024, 5:31 p.m. EDT "Knox Goes Away" was originally reviewed out of its world premiere at the 2023 Toronto International Film Festival.