Alcatraz Producers Come To Stroke Victim's Rescue

According to sources, the car was parked on a street where the crew needed to film -- so producers tried to locate the car's owner ... and traced it back to a house on the block.

When producers knocked on the door, we're told a young woman answered, and informed producers her mother had just suffered a stroke and she didn't know what to do.

According to sources, producers notified several on-set SF police officers -- who then rushed into the house, where the woman's mother was located. Soon after, an ambulance arrived and transported the woman to a nearby hospital for treatment.