NEW YORK (CBSNewYork) — A mystery is brewing in Washington Heights — someone, feeling perhaps a pang or two of guilt, returned an overdue library book nearly 55 years late.

So just who is this hardened criminal? CBS 2’s Don Dahler went out on the case.

The book recently found its way back to the Fort Washington Public Library on West 179th Street. Jennifer Zarr is the library manager.

“I was checking the mail and I saw a mysterious package, and so I opened it up, and here it was,” she said.

Intrigued, she opened the cover of the copy she had received of The Fire of St. Francis Xavier by the Rev. Arthur R. McGratty, S.J.

“On the front page, there’s one of those old cards, and it says it was due April 10, 1958,” she said.

That amounts to 54 years and nine months of illegal possession of an overdue library book. It vastly exceeds the mere 20 years that the fictional version of Jerry Seinfeld kept a copy of Tropic of Cancer in a 1991 “Seinfeld” episode.

These days, books are checked out electronically. The library knows who you are, and if you turn it in late, you pay a fine.

But the card the literary scofflaw signed decades ago is long lost, and the envelope had no return address.

Zarr said the scofflaw is “most likely” looking to stay anonymous, and given the nature of the crime, it’s easy to understand why.

So maybe there are clues to be gleaned from the subject of the book itself. St. Francis Xavier was one of the most prolific Roman Catholic missionaries since St. Paul.

He traveled all over the world, and once advised a colleague to “converse with sinners, making them unburden themselves to you. These are the living books by which you are to study… I do not say that you should not on occasion read written books.”

Well, that must be it then. Whoever the borrower was just took St. Francis Xavier’s advice about reading books. Or, of course, it could have been behind the borrower’s dresser for 50 years.

Whoever it was, they needn’t have worried about the fine. The library said the most it would be was the replacement cost of the book.

But if the library applied current overdue penalty of 25 cents per day retroactively back to 1958, the fine would come to nearly $5,000.

Any long, long, long overdue library books lying around in your closet? Leave your comments below…

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