In case you’re still lost as to what the heck is going on, a Scientology Run is when people film themselves charging into a Church of Scientology building to see how far they can get before being caught and booted out. It’s a notoriously secretive religion, so it turns the whole place into an action-movie set piece where the protagonist is trying to infiltrate a compound while fending off its legion of foot soldiers, clad in terrifying white button-ups with black vests.
Or even just getting hit in the head by a well-meaning person who reasonably thinks they’re trying to prevent a maniac from killing someone in the building.