 The personal lives of the protagonists begin to spiral out of control . Michael 's increasingly erratic behavior prompts his family to leave him , and his attempts to make something of himself bring him into conflict with Devin Weston , a self @-@ made billionaire venture capitalist and corporate raider who develops a grudge against him . Weston vows revenge after his lawyer dies in an accident that Michael is blamed for . Franklin rescues his friend Lamar Davis from gangster and former friend Harold " Stretch " Joseph , who repeatedly attempts to kill Lamar to prove himself to his brethren . Trevor 's reckless efforts to consolidate his control over various black markets in Blaine County see him waging war against the San Andreas chapter of The Lost outlaw motorcycle club , a number of Latin American street gangs , rival meth dealers , government @-@ sponsored mercenaries and Triad kingpin Wei Cheng . 
