VIDEO: How serial stowaway Marilyn Hartman slips past airport security

Serial stowaway Marilyn Hartman has been busted again, trying to sneak through airports in Chicago. But it was here at the Minneapolis airport in January that surveillance video obtained by Fox 9 shows how Hartman pulls it off.

The video shows Hartman snuggling close to a man in line in front of her, like they're traveling together, as she slips past the TSA agent. But the agent notices her, and pulls her back to see her boarding pass.

Hartman fumbles around in her purse for a few minutes, as if she's looking for her ticket, and then slips away. Airport police would find her an hour later, sleeping on the mezzanine level above ticketing. After checking her ID, police soon realize she's the infamous "serial stowaway."

Hartman was also stopped last November at MSP Airport, telling police she was "homeless, bored and looking for a place to read." She is, from all accounts, always polite, frequently apologetic and the sweet grandmother type.

Charges in Minnesota were placed on hold after a mental health evaluation. That was the same story in Jacksonville, Florida, where Hartman was released from jail in April after she was found incompetent to stand trial.

Marilyn Hartman tells investigators she feels safe at airports, even as she exposes how unsafe we all may be.

The legal system clearly doesn't know quite what to do with Hartman. She's too mentally ill to lock-up and be held accountable, but then she walks away from mental health facilities. This week, the 63-year old is in the Cook County Jail, and the process begins all over again.