This is a paperweight.

Except yesterday, it wasn’t.

Yesterday, this was a crown jewel in a highly secured wing of a museum. The internationally renowned and infamous thief Plum and her trusty dog, Apple, were intent on stealing the precious gem. The only people who stood in her way were the night guards, Mia and Olive.

International jewel thief Plum was too tricky for Mia and Olive, though. She plucked the diamond from the display case and fled. When Mia and Olive discovered it missing, they stormed after Plum in hot pursuit. They had an unfortunate surprise when they learned Plum not only was a thief, but a witch as well. And Apple was not her only loyal protector — the dreaded criminal Dr. Bear was on her side, too!

Dr. Bear attacked Mia and Olive to allow Plum time to escape. It looked like the end for the brave museum guards …

Until Superman arrived with his cape flapping and crushed Dr. Bear under a boulder. Olive was able to retrieve the jewel and return it to its rightful place. Mia arrested Plum and put her in jail.

This is what happens when my nieces come over to play. A paperweight becomes a priceless diamond. Sarah becomes an international jewel thief. Katy becomes Deputy Mia, and I become Chief Olive, and Derek becomes Superman with a Doctor Who-blanket cape. Stuffed animals become guard dogs and the dreaded Dr. Bear, couch pillows become boulders, and a closet becomes a jail cell.

Unplugged imagination at its finest.

The day was supplemented with softball in the backyard, trying to coax Webster out from under the bed, a few rounds of Super Mario Bros. and Wheel of Fortune on the Wii, and an abandoned viewing of Disney’s “Frozen.” But the highlight of the day (at least for me) was when they asked, “Aunt Julie, can we play imagination in your house?”

I can’t wait to find out where their imaginations take them — and me — next.