After abandoning his family, a reclusive fugitive must come out of hiding in order to save his son, who has been kidnapped by his vengeful ex-partner in crime.

After his vengeful ex-partner in crime recruits his son for a dangerous heist, a reclusive fugitive must come out of hiding and take his place in order to save him.

After his vengeful ex-partner in crime recruits his son for a dangerous heist, a reclusive fugitive must come out of hiding to save him.

"After his son is kidnapped by a vengeful ex-partner, a gangster who faked his own death to protect his family must now come out of hiding to save his only child."

Quick fix up:

After his ex-partner in crime kidnaps his son, a reclusive fugitive must hunt down the hideout to save his boy's life.

Start with the inciting event then describe the MC and goal. In this instance, the action seems unclear. What is the MC going to do in order to save his son?