Will have three playable characters -- Michael, Trevor and Franklin. Players will switch between characters “constantly” with a single button press, allowing them to see missions from different perspectives.
Michael is a retired bank robber in his early 40s who is now in the witness protection program, and whose wife has burned through his substantial fortune, causing him to get “back into the game.”
His friend Trevor, the second protagonist, is around the same age as Michael and described as a “drugged out psychopath” who's a career criminal and prone to violence.
The final character, Franklin, works as a repo man and is younger, in his mid 20s. Franklin is described as "the young and capable one of the bunch." All three come together to perform heists, which are described as “a big theme in the game.”
Players will experience missions as different combinations of the three characters, and each will have a different skillset. For example, in one heist mission, Michael rappels down the side of a building while Franklin uses a sniper rifle from afar and Trevor flies in a helicopter above. Players can switch back and forth between Michael grabbing a target inside the building or Franklin trying to snipe enemies inside. Once you escape, the player can choose to fly the getaway helicopter as Trevor, snipe other pilots as Franklin or fire a gun from the back of the vehicle as Michael.
Rockstar has also changed driving mechanics, noting that cars “hold to the ground a bit better” and have “a little more physics on them,” making driving feel more like a racing game. Shooting and melee combat have also been improved, as have pedestrian models (some pedestrians have now been mapped using motion capture for more realistic movement).
Characters can be customized by changing clothes, but height and weight customization isn’t included. The phone will also return for obtaining important info, but will now be more modern, with features more like what you'd see on a smartphone. Some items previously only accessible from the phone in Grand Theft Auto IV will simply be accessible on the map.
Each character will have their own social circle -- Michael has his wife and son (Amanda and Jimmy), Franklin has a "crazy friend" named Lamar and Trevor has a paranoid conspiracy theorist friend named Ron. Separately from missions, players will be able to switch between characters and see them living their daily lives. You'll be able to switch between characters at any time when you're not in a mission. Each character also has unique hobbies that only they can participate in, though Rockstar is still "ironing out all the details" on exactly what those will entail. There also won't be romance in the game as there was in Grand Theft Auto IV, and while there will be multiplayer, Rockstar hasn't released details just yet.
Los Santos will be the biggest open world in Rockstar's history, "bigger than Read Dead Redemption, Grand Theft Auto IV and San Andreas combined." Players will also be able to explore underwater areas of the city.
Players won't be able to own real-estate, but there will be plenty of other things for them to spend their money on. There will also be appearances from characters from Grand Theft Auto IV and Episodes from Liberty City -- just not major characters like Niko Bellic. Rockstar explains that the five Grand Theft Auto games on PlayStation 2 are one universe, while Grand Theft Auto IV and V exist in a separate, "high definition universe," so don't expect to see C.J. or Tommy as there won't be any crossovers.