The story is fiction. These aren't.
Every part turns on a real money rule. Here they are in plain English, with sources. US federal rules, not legal advice.
What happens if you deposit more than $10,000 in cash?
In the US, the bank files a Currency Transaction Report (CTR) with FinCEN for any cash deposit or withdrawal over $10,000 in a day. It's automatic and routine. Filing one doesn't mean you did anything wrong.
Seen in Part 1Is it illegal to deposit $9,000 at a time to avoid the $10,000 report?
Yes. Splitting cash into smaller deposits to avoid a bank report is called structuring, and it's a federal crime on its own, even if the money itself is legal.
Seen in Part 2 & 3What happens when you pay more than $10,000 in cash for something?
The business has to file IRS Form 8300 within 15 days, reporting the buyer's name, address and taxpayer ID. Related payments that add up to more than $10,000 count too.
Seen in Part 1What is bait money?
Bait money is cash a bank keeps in teller drawers with every serial number written down. If it's handed over in a robbery, those bills can be traced when they turn up.
Seen in Part 2Can you exchange moldy or rotten cash?
Yes, through the Bureau of Engraving and Printing's Mutilated Currency Division. You mail it in with a letter that estimates the value and explains how it got damaged.
Seen in Part 2Are safe deposit boxes private?
The bank can't see what's inside, but it keeps a record of every visit and the vault is on camera. What's inside also isn't covered by FDIC insurance.