This story is almost unbelievable. Watch the video above to see for yourself.

One Ohio couple began renovations on their basement. The ceiling of the basement needed to to be replaced. That is when they spotted the old lunchbox. It was wedged up between the ceiling and the floor above.

Inside the lunchbox they found three bundles, rectangular in shape, and wrapped in what looked like wax paper or some sort of plastic. They opened the wrappers to find thousands of dollars. The denominations were in $50 and $100 dollar bills, printed between 1928 to 1934. Some of the bills were a type that had never been circulated. This means that the money could be worth more than face value.

Also inside the lunchbox was a newspaper clipping. Was that a clue? It was the Cleveland Plain-Dealer, their town newspaper. The article that was cut out of the paper was from March 25, 1951. That was 65 years ago.

At this point, they decided to call a lawyer. The lawyer told them the value of this money, was around $23,000! The couple wanted to spend this money on home renovation.

But more surprises were about to be uncovered that would lead to the FBI's involvement. 

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In the ceiling they found another old lunchbox. It contained more money. A lot more neatly organized too. That stash was valued at around $45k.

So, what was going on here? Did some former owners simply not trust banks?

BUT WAIT - It gets stranger!

There was a small door that the realtor said probably had the water heater behind it. She was wrong. They found a crawlway with padding laid on it. That led to what appeared to be a hidden panel. A room within a room.

Over in the corner there was what appeared to be a combination lock that seemed like a homemade safe.

That is when they saw the briefcase. Inside the briefcase - a couple of watches, some old paperwork. No money.

BUT WHAT WAS IN THE SAFE? The first item pulled out of the safe was a piece of paper that had messy writing that read "save yourself" in dripping black ink.

The rest of the contents were videotapes with a note that simply said, "DO NOT."

Weeks went by before the couple was finally able to find a tape player that could play these old videotapes.

What was on those tapes prompted the couple to call the FBI. Apparently, the case was serious enough that the couple wasn't allowed to discuss it in public. They had been updating the renovation of their house on Facebook. All of that was taken down.

The couple finished renovating their house. Neither the FBI nor the couple will talk about what was on the tapes.

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