This mission starts at Michael's house. The first four minutes of this mission are cut scenes. Michael is feeling good about himself after the successful jewelry heist and wants to celebrate. He asks Amanda out to dinner but she blows him off and heads off to her "yoga lesson". Franklin shows up and the two of them have drink to celebrate as Michael explains Lester is going to unload the jewels and they should have a good haul after paying Mendroza(verify Name). Dave the FIB agent shows up right after they toast and is obviously worried. He seems pretty certain that Michael pulled off the heist and is worried about Michael popping up on Trevor's radar. Michael doesn't seem too concerned about Trevor and half-heartedly denies being involved in the heist. Dave turns on the TV and the heist is all over the news....
......the scene changes to a new location with the same news cast playing and we are finally introduced to Trevor in his trailer in Blaine County. Trevor is busy having "relations" with Ashley Butler who is a returning character from The Lost and the Damned (GTA IV add on story) who had a substance abuse problem. The news reporter is interviewing the man Michael bumped into when leaving the Jewelry store during the heist and he repeats on the news what Michael said to him "People forget thousands of things each day, make sure this is one of em". Trevor hears this line and stops and stares at the TV. He zips up and seems very distracted and starts pacing around his trailer lost in thought. The scene cuts to outside and Johny Klebitz (name verify) the Protagonist from The Lost and The Damned is approaching with Wade and Ron (Trevor's business associates) trying to stop him. Johnny calls out Trevor for having sex with his girlfriend in exchange for drugs. Johnny is obviously angry with Trevor but Trevor, lost in thought, ignores him and walks right past him and up the road. Johnny runs after Trevor and confronts him and Trevor finally acknowledges him and Johnny admits that he loves Crystal and that it isn't right. Trevor softens his tone for a minute to put Johnny at ease and then throws him to the ground, hurtles a beer bottle at his head and then murders him brutally by kicking him repeatedly in the head. Trevor then screams at Johnny's body and curses at him about getting in his face and mentions he just saw a ghost (Michael) he then starts walking toward his truck and the cut scenes finally end.
Trevor, Wade, & Ron all get in Trevor's truck and Trevor mentions that Johnny forced his hand and they need to find the rest of The Lost, presumably before they find out about Johnny and come after Trevor. As you drive toward a way point Trevor instructs Wade to find Michael Townley in Los Santos. They arrive at a farm and there are several members of the lost there including Terry and Clay from The Lost and the Dammed. During a cut scene, Trevor in a brief discussion with them informs them that he just killed Johnny. The don't believe him but jump on their bikes and in a Van and head off. Trevor follows them hoping they lead him to the rest of the gang. Trevor chases them to a trailer park taking out Terry and Clay on the motorcycles on the way. They arrive at the trailer park on the edge of the Alamo Sea that is crawling with members of The Lost.
Trevor tells Ron and Wade to "hold the perimeter" and Trevor's objective is to go through the trailer park and takes out all the members of The Lost. Use the cover system (hiding behind objects and around corners) and Trevor’s ability as needed to clean out all members of The Lost from the Trailer park.
You get back in Trevor's truck and then head toward another way point. Trevor informs them that they are going to "drop in" on Ortega. Ron tries to tell them this is not necessary, that there is enough business for all of them but Trevor is intent on removing some of his competition. When you arrive at Ortega's trailer it is parked at the top of hill near a small river. You are instructed to push the trailer down the hill and into the water with Trevor's truck. After this is accomplished there is a brief cut scene with Ortega in the water and Trevor informs Ortega that he is out of business and The Lost MC are out of business and that the drugs and guns in this area go through Trevor Phillips Enterprises only. Ortega briefly protests and Trevor puts him down. You then return to Trevor's trailer.