As you're talking with Beverly, he spots a celebrity getting into her limo and wants you to help him get some shots of her. Get onto the bike and chase after the limo, pulling up along the side of it to let him get some pictures. Keep doing this until a rival paparazzi appears and starts taking some pictures of his own. Beverly wants you to get close enough to this guy, so he can smack him off.
That means ignore the limo and continue chasing after the rival. You can see that the guy is pretty fast, so use your special ability to get close enough to let Beverly knock him off his bike. Once you do, drop Beverly off at the marker to finish the mission.