Three little boys tumble down a grand staircase, shouting and laughing, pulling each other back. Each wants to be the first to reach the bottom and skid across the floor.
"Wait for me!" shouts 5-year-old Victor as his brothers disappear. He races after them into a dark closet.
Victor grabs the run of a ladder and climbs a ladder to a crawl space above. "Grant! Marc! Wait."
He spots 12-year-old Grant framed in the light from a ventilation shaft. Grant is peeking through the slot, watching his parents working below. Nine-year-old brother Marc crawls through the dark to another spy hole.
The three brothers live in a magical place riddled with secret tunnels: a 35,000-square-foot building their parents are restoring, mostly by themselves.
That's right: a home one-third the size of Downton Abbey. Except without the downstairs help.
And their mom and dad, Erica Farmer and Marc Whitacre, couldn't just slap on a coat of paint and move in: Their home is one of America's treasures: an abandoned post office in Havre, Montana, that's on the National Register of Historic Places.
After it was closed in 1995, winter crept inside. Pipes froze; paint flakes fell like snow, covering the ruined hardwood floors.
Erica and Marc bought the rundown post office three years ago. They paid about what it costs for a four-bedroom, one-bath home in Havre. "When did you start having second thoughts?" I ask as Erica and Marc strip a generation of gunk from the floor.
"Never," Marc replies. "We had fixed up an old home before. and knew what it would take."
The old post office has some unique features. "Why is that safe up by the ceiling?" I ask Erica, pointing to a bank-size vault 21 feet above us.
"That's where they kept the money," she explains."They figured a burglar would be easier to catch if he had to bring a ladder."
The large air ducts the kids are looking through allowed post office cops to keep a close watch. The inspectors could roam unnoticed in dark tunnels throughout the building. Hidden eyes could even see who washed their hands in the bathroom.
Dustin Kinsella once worked in the old post office. "I never used it," he says with a laugh about the secret tunnel system.
"Did you know you were being spied on?" I ask.
"We heard rumors."
The family has been living in the basement while doing the repairs upstairs. Marc had to become a state-certified boiler repairman to keep them warm. "Wouldn't it be more fun to have an acre or two and play cowboy instead of building super?" I ask him.
Erica jumps in with a question of her own. "Am I ready to move out of the basement? Oh, I'm ready!" She glances up at their basement window, where the shadows of feet are passing by.
At least Erica manages to give Marc a nice view of Montana's big sky country: She taught herself to operate a bucket lift, so Marc can repair the building's third floor windows. "I still get a little nervous," she admits.
They bought the battered old bucket truck from a bank for just $7,000. Marc dangles three stories above us in a 36-year old rig that had been repossessed.
Like most do-it-your-selfers, Erica and Marc are restoring the old post office in their spare time. What are their day jobs? Eye doctors. Erica's an optometrist, and Marc is the only eye surgeon in 150 miles. "Doesn't your eye practice keep you busy enough?" I ask.
Marc laughs. "You have to have something to think about while you're working."
Marc loves learning: He can speak Japanese, Chinese, Spanish and French and has a master's degree in Asian studies. And Erica thrives on technical challenges: She moonlighted with the Army Corps of Engineers while going to school.
"What's next?" I ask. "Re-plumbing the Grand Canyon?"
After all this work? Marc and I are standing next to an elevator control panel he's just restored. Its clicking like an old clock. The elevator doors open and his family spills out, carrying furniture and clothing. They're finally moving from the basement to the building's top floor, where a courtroom was added in the 1930s to handle the overflow of bootleggers smuggling illegal booze into the country.
The holding cell is now a closet. I touch the bars and ask 5-year-old Victor: "Is this the time out room?"
He mimics a reporter's voice: "Is this the time out room?"
"What are you: a parrot?" I reach through the bars and tickle him. He dissolves in laughter.
The judge's chambers will be Marc and Erica's new master bedroom. They've opened the rest of the floors for others to enjoy. The old mail sorting room has been restored for wedding receptions. Couples now marry in the lobby in front of mail slots that bear their family names.
Many landmark buildings in America have been saved by people with vision and money. This one was pulled from history's scrapheap by sweat and unpaid labor, by the kind of family that could make the faces on Mount Rushmore grin.
"We're just saving this place for the next generation," Erica says, touching a lamp. "We're like lighthouse keepers."
Exactly: the ones who show the rest of us the way.
Do you know someone outstanding? To suggest a topic for a future American Story, visit Bob Dotson's Facebook page.
Learn about Bob Dotson's book "Make It Memorable: Writing and Packaging Visual News with Style."