To prepare for the scene in "The Matrix" (1999) where Neo wakes up in a pod, Keanu Reeves lost fifteen pounds and shaved his whole body to give Neo an emaciated look.
Will Smith turned down the role of Neo to make "Wild Wild West" (1999), because of skepticism over the film's ambitious bullet time special effects. He later stated he was "not mature enough as an actor" at that time, and that if given the role, he "would have messed it up." Smith praised Reeves for his portrayal.
Nicolas Cage also turned down the part because of "family obligations." Warner Bros. sought Brad Pitt or Val Kilmer for the role. When both declined, Leonardo DiCaprio initially accepted the role, but ultimately turned it down because he did not want to do a visual effects film directly after "Titanic" (1997). The studio pushed for Reeves, who won the role over Johnny Depp, the Wachowskis' first choice. Lorenzo di Bonaventura stated that the screenplay was also sent to Sandra Bullock, with the suggestion of rewriting Neo as a female.
Prior to pre-production, Reeves suffered a two-level fusion of his cervical spine, which had begun to cause paralysis in his legs, requiring him to undergo neck surgery. He was still recovering during pre-production, but insisted on training. Stunt coordinator Woo-Ping Yuen let him practice only punches and lighter moves. Reeves trained hard, and even requested training on days off, however, the surgery left him unable to kick for two out of the four months of training. As a result, Reeves did not kick much in the film. (IMDb/Wikipedia)
Happy Birthday, Keanu Reeves!