When a Massachusetts grandmother picked up the phone, the voice on the other end sounded like her teenage grandson.
The caller, who knew Fran Shea's grandson's name, said he was in trouble. He'd been in a car accident and alcohol was involved. He'd also spent the previous night in jail.
Begging her not to tell anyone, the caller then passed the phone to a person he said was his public defender.
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"It was very convincing," Shea recalled. "All I want to do is get him out of jail. If they found out at school, he'd be off the hockey team. Everything would be ruined."
The 83-year-old Lexington woman carefully wrote down the instructions from the person who claimed to be the public defender.
Shea then rushed to the bank to withdraw $8,000 cash. Back at home, she placed the money inside the pages of a magazine before placing it in the shoe box, as the caller had instructed.
She wrapped the package in Christmas paper and then called neighbor Beverly Tringale to ask for a ride.
"It was a very frantic call," Tringale said. "I get to her house and she's in tears. She said she needed a ride to FedEx. I asked what was going on. She said, 'I cannot tell you.'"
Tringale continued to press for details, but Shea refused to shed light on the situation.
At the FedEx store in Burlington, Shea opted to pay more than $180 for overnight delivery to a strange address in Florida.
Visibly concerned about the situation, the FedEx employee started asking questions. She eventually told Shea a story about a grandmother who'd lost thousands of dollars to a scam after believing she needed to help her grandchild.
"That's when it clicked in my head," Shea said. "I realized it was a scam. Thank God she started asking questions."
A FedEx spokeswoman told NBC10 Boston the company does not permit the shipping of money.
"We're thankful our team member was able to help our customer avoid this situation," the company said in a statement.
The so-called "grandparent scam" has been around a number of years, but it has grown more sophisticated in recent years, thanks to personal details that can be discovered via social media.
"There is usually some nugget of truth to what people are saying to you," said Middlesex District Attorney Marian Ryan. "We are seeing a lot of these cases with some substantial sums of money."
According to the Federal Trade Commission, victim losses from these family impostor scams have resulted in more than $41 million this year. That's a large increase from $26 million the previous year.
People ages 70 and over report losing a median amount of $9,000, typically in cash sent through the mail.
Ryan, who visits senior centers to raise awareness about the scam, said it's so effective because it preys on emotions.
"Grandparents love their grandkids, and they will do anything to help," she said.
Shea said fear of her grandson's well-being definitely prevented her from slowing down and thinking rationally. She is now hoping her close call will serve as a warning to others.
"Check with someone. Don't stay quiet," Shea said. "I feel bad for anyone this happens to, and I can picture a lot of other grandparents going through the same thing."
Ryan Kath can be reached at email@example.com. You can also follow him on Twitter or connect on Facebook.