You'll hook up with Jim and Terry again, this time meeting with GTAIV main-story character Ray Boccino. Ray needs a steady flow of "merchandise," and this civil war within the Lost MC is detracting from that. As he states, it's in his best interests to help out Johnny and crew in order to get things back in order so the steady flow can continue. The traitorous Brian has been located, holed-up in a safehouse in southern Alderney with a small squad of goons for protection. Johnny decides that the time has come to put an end to Brian's backstabbing ways for good. Upon arriving at the safehouse, Jim informs you that you can call either Terry or Clay for backup. Phoning either of the two will bring both to the scene.
It's at this point you need to make a choice - you can call for backup and the mission goes down a different way. Alternatively, you can "lone wolf" the job and have it play out in another way. If you go the backup route, you'll be instructed to shoot a grenade into the second-floor window on the right of the front of the safehouse. This will make all the enemies stream out of the building through the back door, where Terry and Clay are lying in wait. If you go the lone wolf route, you'll be going through the house systematically killing all the Lost MC traitors inside. Once they're all dead, you'll find Brian hiding in a back room on the second floor. At this point, bring a weapon up to him and you're treated to a cutscene execution. Johnny tells Brian to stop being a bitch for once and take what's coming like a man. With that, Johnny shoots him in the chest and Brian's revolution is over.
Note: Completion of this mission awards you with Brian's safehouse to use as your own. There's parking in the front, and a bed upstairs in a back room near to where Brian was killed. Unlike the Lost MC clubhouse, this safehouse is devoid of anyone except yourself. The radio station LCHC is staying playing extremely loud throughout the house like the clubhouse. There's no internet access or any of the other bonuses found within the Lost MC's clubhouse.