"Catch Jimmy" is an objective in the story mission Father/Son in Grand Theft Auto V.
Walkthrough[edit]
Jimmy makes it out onto the deck. Just a little after that, he learns a bit about why the boom is called that. He gets knocked over the side of the and is hanging onto the boom.
To catch Jimmy you need to get the car underneath him. Use his shadow to get the car in the right position and he will drop after a few seconds. Remember, it takes a moment for him to be sure enough that you will catch him.
