Hello SideDorables, it's October, and here in DC the air is getting crisp, the leaves are falling off the trees, and Halloween is just around the corner.

Which is why we wanted to share the spookiest episode of SideDor ever made, and one of my personal favorites.

I recommend listening sometime after dark, in a quiet place.

Maybe with some hot tea and a blanket and a few choice pieces of fun-sized candy close at hand.

I hope you'll enjoy it, and try not to get too scared.

This is SideDor, a podcast from the Smithsonian with support from PRX. I'm Lizzie Peabody.

This is the stairwell in question. Here we go.

This story begins in a stairwell, and we'll come back to that stairwell in just a moment.

But first, I need to tell you a little story.

A little while ago, I was at the Smithsonian's National Museum of American History for an interview.

As I followed the curator through a staff door and into a little old elevator and down a narrow hallway toward her office, I started to wonder how it would feel to be in here alone.

In the bowels of the museum, all by yourself, with the long hallways and the buzzing overhead lights in the dim corners and the quiet.

So I asked her, do you ever feel ill at ease when there aren't visitors around?

No, she said, but I do have a colleague who saw a ghost once. Totally matter of fact.

We went on with our scheduled interview, but the prospect of a ghost lurking the halls of American history kept tugging at the back of my mind.

I thought about it every time I visited the museum. Until I decided, I needed to know more about this ghost.

Which is why we're in a stairwell in the National Museum of American History, with Molly Horox.

I'm the collections manager for the exhibit that's right under this staircase, the price of freedom, which is an exhibit about a war, basically.

Molly works as the collections manager for military history. And one morning, a few years ago, she came in early.

She was meeting with a mount maker, somebody who builds display mounts for objects in an exhibition.

It was probably like 830 or so, because we like to do things when people aren't around.

So I'm leaving my office. I've got my keys, I've got my supplies. I'm meeting our mount maker at the case, which is right at the end of this stairwell.

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