John Wick’s script was initially written with a 75-year-old man as the titular character

Keanu Reeves entirely hijacked John Wick which was different from the original plan. Initially, the movie was set to release with a different name but the actor did active promotions with his titular character’s name leading the studio to move ahead with ‘John Wick.’ It happened after he made a great change in the film script after showing interest in playing the role.
Keanu Reeves

The ‘John Wick’ Title is Keanu Reeves’ Work 

Keanu Reeves in a still from the John Wick franchise
John Wick scriptwriter, Derek Kolstad who also worked on its sequels, John Wick: Chapter 2 and John Wick: Chapter 3 – Parabellum revealed to Comicbook.com about the change in the movie name. Originally, the movie was titled ‘Scorn’ but Keanu Reeves kept taking the movie name wrongly in several public appearances. 

Kolstad shared, 
“The only reason it’s called John Wick is that Keanu kept referring to it as John Wick.” 
The scriptwriter explained that the marketing team eventually went ahead with the new title since promoting it with its original title would have been too much of a hassle. 
“Marketing was like, ‘Dude, that’s four to five million dollars in free advertising so far, so it’s John Wick instead of Scorn’. I can’t imagine it being Scorn now.”
Eventually, Reeves’ mistake of taking the names wrongly in several interviews led the movie to be named John Wick. Not just the name but Reeves has quite an influence on Scorn script’s original concept as the titular character was initially 75 years old, with actors like Clint Eastwood in mind for the role. 

John Wick’s Script Was Written With Clint Eastwood in Mind

Clint Eastwood
John Wick producer, Basil Iwanyk in his book, They Shouldn’t Have Killed His Dog: The Complete Uncensored Ass-Kicking Oral History of John Wick, Gun Fu, and the New Age of Action revealed that that lead character was “a 75-year-old man.” Considering the age, the role was written for actors like Harrison Ford or Clint Eastwood. 

He wrote in the book via EW, 
“One of my best friends is Charlie Ferraro at UTA, who sent me this script from Derek Kolstad called ‘Scorn.’ The lead was a 75-year-old man, 25 years after being retired. It was the fun of watching Clint Eastwood kick a-s. I thought, ‘Okay, there’s probably one or two names you could do this with Clint Eastwood, Harrison Ford.’”
He continued that the script got the Speed actor’s attention who made the changes to fit into the role. 
“He read [the script] on a Friday, in 90 minutes, and was like, ‘I want to do it.’ At that moment, before I met and really clicked with him, I was like, ‘Yeah, I really want to do it, too.’ The first thing that Keanu said to me was, ‘Okay, Derek, I’m going to play him 35.’ And I’m like, ‘Fine.’”
His sheer dedication eventually convinced the writer to change the character’s age to make it younger. According to Kolstad, the Neo fame “got his talons into [the script] and made it his own.” He eventually raised the bar by playing the role of a retired hitman who dives into the dark world he once left only to get intertwined into a chain of events. His portrayal gained wider acclaim from critics and fans with John Wick: Chapter 4 hitting the theatres this summer. 

The fourth installment of the John Wick franchise is available to watch on Starz.