One often points to the MCU regarding how the studio could construct such a massive connected universe, while Rockstar Games have done the same with GTA.
The GTA franchise, in many ways, represents the very best that the AAA games industry has to offer with regards to quality, scale, and value. One of the franchise's biggest achievements has been telling individual, independent stories while also being able to tie them all together.
Meaning, every single game takes place in the same universe, and characters appear in multiple games. Depending on the timeline, characters are often younger or older than when they first appeared.
5 characters in GTA 5 that appeared in previous games in the franchise
5) Johnny Klebitz
In perhaps what has become one of the most iconic character introductions in a video game ever, Johnny Klebitz from GTA IV: The Lost and Damned meets his rather unfortunate and brutal end. While not a straight arrow by any means during GTA IV expansion, Johnny finds himself truly off the rails during Grand Theft Auto's events.
Johnny is but a shell of the man he used to be and finds himself at the mercy of his addictions. After getting into an altercation with Trevor, the character has his head brutally stamped into the ground.
One of the biggest swerves pulled by Rockstar Games in GTA IV is the revelation that Michelle, whose real name is Karen, was indeed an undercover IAA agent. The revelation ends with Niko and Karen breaking up, and she wasn't seen for the rest of the game.
However, during the mission "By the Book" in GTA 5, she appears as the agent interrogating Mr K and threatening him with a flashlight. A cameo adds weight to a connected universe.
3) Patrick "Packie" McReary
Perhaps one of the best missions in GTA history, Grand Theft Auto IV's "Three-Leaf Clover" laid the groundwork for the Heist system in Grand Theft Auto V. One of the most likeable presence to have around during the mission and the rest of the game is Packie McCreary.
During a Random Event in GTA 5, he appears where the player encounters two men sticking up a drug store. The player can then choose to drive them to safety. He will become available as a Gunman for Heists in the game, which is neat.
2) Rocco Pelosi
Initially appearing in the franchise as one of GTA IV's main villains, Rocco Pelosi is an incessantly annoying and despicable character. So when he gets punched into oblivion at Michael's hands in GTA 5, it feels all the more satisfying.
He appeared in the game as a talent agent attempting to pry away Richard Solomon's actor and director. Michael foils his plans with the aforementioned punching and flies the talent back to Richard.
Purely by the number of credited appearances, Lazlow has probably appeared numerous times throughout the franchise. Initially having only appeared as a radio host, Lazlow appears as a fictionalized version of himself in GTA 5. He is the host of the infamous reality TV show Fame or Shame.
His appearance in the game was extremely chuffed about as he played an extremely exaggerated version of himself. Apart from his performance, Lazlow had also been involved with GTA's creative process GTA regarding writing.
He would also go on to work on Red Dead Redemption 2 as a writer and audio director.