John Carpenter's Tales of Science Fiction: Civilians #2

Plot

You're taking a shower. Nothing more normal in the world, right? But wait. This is not your shower; this is not your bar of soap; hell, this isn't even your apartment. You have no idea how you ended up here, naked. But things are about to get far worse as you step out of the shower and leave the apartment (still naked, still dripping wet) and somehow end up in a violent riot on the streets of Beverly Hills.