This is 99% invisible. I'm Roman Mars.

The Belvue Stratford Hotel opened in Philadelphia in 1904 and quickly became one of the most luxurious

hotels of its time.

It was 19 stories high, had over 1,000 guest rooms

and what was said to be the most lavish

and magnificent ballroom in the United States.

It also featured light fixtures designed by Thomas Edison and a grand marble staircase.

The hotel came to be known as the Grand Dam of Broad Street.

And for years, the Grand Dam was the center of high society culture in Philadelphia.

It hosted presidents and Queens and all kinds of other rich and famous guests.

That's producer Alana Gordon from W H Y Y's The Pulse in Philadelphia.

The hotel went through some harder times during the Great Depression and then again in the 50s and 60s.

It lost some of the prestige from its early days,

but it was always considered one of the nicest places to stay in Philadelphia.

That is until the mid-70s, when the Bellevue-Stretford Hotel became the epicenter of a series of mysterious deaths that terrified the country.

It all started in July of 1976 when more than 2,000 veterans descended on Philadelphia

for the Convention of the American Legion,

a support organization for wartime vets.

The statewide convention happened every year, but in 1976 was a really big deal.

The time and place of the convention had been chosen to coincide with the 200th anniversary of the Declaration of Independence, signed in Philadelphia in 1776.

And the Convention would be held in, you guessed it, the Bellevue Stratford Hotel.

The gathering was going to be a big party for the members of the American Legion, a chance for the

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