In a six-page report filed with the Highland Park Police, Mr. Poniz described the watches, coins, documents and other items that were gone. Using auction records and sales reports, he estimated that their combined value was more than $10 million. That would make it one of the largest safe-deposit-box losses in American history.

Jason Bourne is not the norm

Moviemakers love safe deposit boxes much more than bank executives do. On film, they’re an essential tool for spies — Jason Bourne, for example, retrieved cash and passports from a Swiss box with the help of a device implanted in his hip — and a magnet for cunning thieves. Cinematic burglars have raided highly secured vaults by tunneling in (“The Bank Job”), drilling through a wall (“Sexy Beast”), disabling alarms (“King of Thieves”), taking hostages (“Inside Man”) or simply blowing off the doors (“The Dark Knight”).

Real-world criminals have tried similarly spectacular attacks. In Conroe, Tex., someone cut through the roof of a bank last year and looted its safe deposit vault. Robbers took a similar route three years ago into two banks in Brooklyn and Queens, where they left empty boxes scattered in their wake. (Four men were convicted of the crime, which netted them more than $20 million in cash and goods.) But such capers are rare. Of the 19,000 bank robberies reported to the F.B.I. in the last five years, only 44 involved safe-deposit heists.

Banks increasingly regard safe deposit boxes as more of a headache than they’re worth. They’re expensive to build, complicated to maintain and not very lucrative. The four largest American banks — JPMorgan Chase, Bank of America, Wells Fargo and Citigroup — rarely install them in new branches. Capital One stopped renting out new boxes in 2016. A dwindling number of customers wanted them, a bank spokeswoman said.

“All of the major national banks would prefer to be out of the safe-deposit-box business,” said Jerry Pluard, the president of Safe Deposit Box Insurance Coverage, a small Chicago firm that insures boxes. “They view it as a legacy service that’s not strategic to anything they do, and they’ve stopped putting any real focus or resources into it.” He estimates that about half of the safe deposit boxes in the country are empty.

The number of bank branches in the United States has been steadily declining — down 10 percent in the last decade — and safe deposit boxes are being relocated, evicted and sometimes misplaced. In Maryland, a large bank closed several branches and lost track of hundreds of safe deposit boxes, according to a lawsuit filed by a customer who said he lost gold and gems valued at $500,000. In Florida, a customer accused Chase of losing her box and all of its contents — coins, jewelry and family heirlooms worth more than $100,000. (She sued; a federal judge ruled that she had waited too long to file her negligence claim and decided in the bank’s favor.) In California, a Wells Fargo customer said the bank accidentally re-rented her box; the diamond necklace and other jewels she had in it were never found.