A star and creator of the FX series “It’s Always Sunny in Philadelphia” – and, most recently, the voice of Luigi in “The Super Mario Bros. Movie,” Charlie Day, makes his feature directorial debut with “Fool’s Paradise,” which can be described as something of an homage to French filmmaker Jacques Tati. Impressively, Mr. Day has managed to wrangle an all-star ensemble including Ray Liotta, Adrien Brody, Kate Beckinsale, Jason Sudeikis, Edie Falco, and John Malkovich to play second fiddle to him and Ken Jeong.  

Mr. Day technically plays two roles here as Kevin Kline did in “Dave,” but his main character is a patient diagnosed with age regression, who has the mental capacity of “a 5-year-old or a Labrador retriever” and no ability to speak. Since the state likely won’t fund his treatment, the institution promptly tosses him “on the first bus downtown.” Though he’s supposed to be a bum, he looks sharp like a hipster with his brown bowler hat, crisp blue dress shirt, and navy wool blazer.  

He happens to be a doppelgänger for an inebriated and incapacitated movie star (also Mr. Day) whose vexed producer (Mr. Liotta) is out driving around and scouting frantically for a stand in. Lenny (Mr. Jeong), a publicist desperate for a new client, steps forward to represent this outcast, whom he calls Latte Pronto, mistakenly thinking that’s his name after hearing the producer barking a drink order at an assistant. At least Lenny seems to genuinely care about Latte, unlike the horde of fair-weather professional leeches such as Latte’s agent (Ms. Falco) and business manager (Glenn Howerton, from “It’s Always Sunny in Philadelphia” and the newly released “BlackBerry”). 

Lex Tanner (Mr. Sudeikis), one of Latte’s directors, shouts “Playtime!” instead of “Action!” on the set, name-dropping Mr. Tati’s beloved classic French comedy. “Fool’s Paradise” itself appears to be something along the lines of Mr. Hulot goes to Hollywood. Mr. Hulot, Mr. Tati’s alter ego in a series of films released within a two-decade span half a century ago, was like a mime from the Silent Era who accidentally wandered into the French New Wave. While himself hugely in debt to Charlie Chaplin, Mr. Tati clearly influenced comedians the likes of Rowan Atkinson.  

Thrust onto the film set of “Billy the Kid,” Latte is utterly clueless and doesn’t take direction at all. The first act of “Fool’s Paradise” mines much slapstick from Latte’s inability to differentiate between make-believe and reality. He cowers at attacks from Billy’s rival, played by Chad Luxt (Mr. Brody), and flinches at angry outbursts from Billy’s love interest, played by Christiana Dior (Ms. Beckinsale). 

Mr. Hulot imbued a sense of wide-eyed wonder in his whimsical adventures. We’ve certainly seen this in a Tinseltown context, memorably in the beginning of “Mulholland Drive.” But it’s missing in “Fool’s Paradise” because Mr. Day doesn’t center the story on Latte’s point of view. Instead there are crane shots of the studio lot as in “The Player,” projecting the opposite of Mr. Hulot’s naïveté. Here, Latte seems more overwhelmed than bemused by his entourage of handlers. Also unlike the modern urbanity in “Playtime,” the Hollywood in “Fool’s Paradise” is nothing resembling the fun rides of an amusement park. 

Mr. Tati famously built the mini metropolis in “Playtime” from scratch, making the film one of the priciest French productions of its time. “Fool’s Paradise” likewise spares no expense. In addition to the impressive ensemble cast, discerning viewers might spot an Hermès throw blanket here and an Eames lounge chair there. But there’s no mention of Mr. Tati in the “Fool’s Paradise” press notes, which makes one wonder if the comparisons to the French icon’s work it invites might be purely coincidental rather than purposeful. 

“Fool’s Paradise” meanders toward the finish line with Latte being recruited by political kingmakers and then kidnapped by the sinister Cote brothers (John Malkovich and Tom O’Rion), undoubtedly substitutes for the Kochs. Rather than exploring the Hollywood-to-politics pipeline of Reagan-Eastwood-Schwarzenegger, the setup hastily culminates in a rather sophomoric punchline. Had Mr. Day delved deeper and done more with it, the ending might not feel quite so abrupt.