One humid morning this past summer, Omeed Dariani drove his black Tesla sedan through the foothills east of San Diego, looking apprehensive. Dariani is the founder and C.E.O. of Online Performers Group, a talent-management company dedicated to professional video-game streamers, who broadcast their game play and commentary live over the Internet. He is thirty-eight, with a dry, ironic wit and a nervous habit of twirling his goatee, which is rapidly going gray; his clients are, for the most part, young, boisterous, and unpredictable. That day, he was on his way to meet the streamer Roberto Garcia, who was supposed to be at home but had instead gone to a casino outside the city to celebrate his girlfriends birthday. Darianis speedometer crept toward ninety miles per hour. We just need to get there before he starts to drink, he said.