The Godfather Part IV was scrapped before it ever really began, but why, and what would've happened in Francis Ford Coppola's planned sequel? Despite being almost half a century old, The Godfather is still revered as one of the finest stories ever put to film. Written by Mario Puzo, the author of the original novel, and directed by Coppola, the crime epic made the careers of its main cast and became a shining example of how to execute virtually every aspect of filmmaking. Unusually, The Godfather Part II lived up to that ridiculously high standard, and some even consider the sequel superior to the original.
For many years, The Godfather stood alone as a two-part masterpiece, but with the franchise's popularity only growing, it was only a matter of time before temptation proved too much for Paramount, and Coppola was roped into making The Godfather Part III not entirely willingly. Released in 1990, The Godfather Part III explored Michael Corleone's attempts to turn the family business legitimate, while a new generation of gangsters led by Sonny's son Vincent (Andy Garcia) rose to prominence. While certainly not a bad movie, Part III paled in comparison to the previous Godfather movies, with a markedly different tone and less of the electrifying performances that had previously defined the series.
Given The Godfather Part III's underwhelming critical reception and Coppola's reluctance to make a third movie in the first place, it's somewhat surprising that the director was planning Part IV. In his DVD commentary for the 1990 movie, Coppola reveals that he and Puzo began hammering out what The Godfather Part IV might look like. According to the legendary director, the next installment would've adopted the same structure as Part II, split between different timelines. In the present, The Godfather Part IV would've continued Vincent's story as the head of Corleone family, presumably with Andy Garcia's character taking over as the face of the franchise. The past timeline would've been set between Robert De Niro's Godfather Part II narrative and the original film, exploring how Vito Corleone evolved from the relatively small-time mob boss who murdered Don Fanucci to the virtually omnipotent figure introduced by Marlon Brando.
Interestingly, the main character of the old New York timeline wouldn't be Vito, but Sonny, creating the same link between father and son that anchored The Godfather Part II. Meanwhile, Vincent would've, somewhat expectedly, led the Corleone family headfirst into the drug trade, poking into the darkest corners of criminality. Haunted by the death of Mary (Sofia Coppola's character in The Godfather Part III), Vincent would also be gunning for revenge and seeking out the last of his rivals, while sharing only a single scene with Al Pacino's retired Michael. Although initial ideas were being plotted out, The Godfather Part IV was never scripted, and was dropped altogether when Mario Puzo passed away in 1999.
In concept at least, this prospective story sounds far superior to The Godfather Part III, offering more of the explosive gangster action that fans were looking for, while also delving back into the classic era, rather than moving fully into a modern age that didn't necessarily evoke the same feelings and emotions. While Andy Garcia and Al Pacino would've been perfectly able to reprise their roles as Vincent and Michael, respectively, for the present-day timeline, casting the pre-WWII story would've been much trickier. The original cast of James Caan, Robert Duvall, etc. would've all been much too old, while John Cazale passed away in 1978. Coppola would almost certainly have had to recast the entire family - a tricky business for such well-loved characters. In the case of Vito, Robert De Niro might have been made to look a few years younger than Marlon Brando, depending on how soon after 1990 The Godfather IV would've been released, but that too would've proved highly controversial.