As they perform larger heists, they are coerced into working for the (a parody of the FBI) by corrupt agents Steve Haines and Dave Norton. These agents use the trio to undermine the rival IAA and conduct dangerous black ops missions. The Climax and Multiple Endings

: A retired bank robber living in witness protection after a botched heist in North Yankton years prior. Despite his wealth, he is bored and frustrated by his dysfunctional family.

In the present day, Michael and Franklin meet when Franklin is tasked with repossessing a car from Michael’s son. After they team up for a jewelry store heist to pay off a debt, the news reaches Trevor, who realizes Michael is still alive. Trevor travels to Los Santos, and the three eventually unite.

The story begins with a set nine years earlier in North Yankton, where a bank heist goes wrong, leading to Michael's supposed death and Trevor's escape.

The story reaches its peak with "The Big Score," a massive gold bullion heist from the Union Depository. Following this, the protagonists are pressured by billionaire Devin Weston and the FIB to kill one another. You must choose one of three endings: