|After finishing The Big Score, switch to Franklin and go to his house in Vinewood Hills. While there, someone will come to the door and you'll see that it's Devin. You will be presented with a choice between three different outcomes; a choice of A, B, or C. To start this mission, choose the B option.|
When you choose this option and the phone conversations end, a "M" will appear on your map. Head there to meet up with Michael, who will end up taking off in his car when he realizes what's going on. Chase after him and be careful when you see the train, as you should stay behind it because of the narrow bridge.
It's not a long chase, as he stops at a nearby factory, so continue chasing him on foot. Note that you have to be careful here, as while you can shoot at Michael, you can't injure/kill him, but he also shoots back and is able to kill you. Keep following him until you get to the top, where a cutscene will occur and you will have the choice between dropping Michael or saving him. Either way, the outcome will be the same, ending with Michael's death and the end of the mission.
|If you choose this option as your first choice for the final mission, then Michael will no longer be playable on that save file. Also, Michael's split from the last heist will go to his family, so neither Frankling nor Trevor will see any of it. On top of that, you will not be able to hang out with Trevor for the rest of that save file.|