Anyone who ever had a flipbook as a child will remember the sheer delight of watching a two-dimensional image appear to move as you fan through the pages.
And now, a man from Chicago has taken this treasured childhood technique and turned it into an epic proposal.
Rodney Nelson proposed to his girlfriend, Alexa Winning, using a flipbook featuring a dog running off to catch a yellow ball and returning with a little black box.
And at the end of the flipbook there was - you guessed it - a diamond ring.
Writing on the website How He Asked, Alexa described her surprise at the proposal, which took place during the Lincoln Park Zoo lights festival.
She said, "It was absolutely freezing but he insisted that we bundle up and go anyways. Right in front of the big light display, he turned to me and told me he needed to give me my Christmas present. I remember thinking 'Seriously, right now? Are you crazy?' but he insisted and showed me a flip book."
"It was perfect because I had to take my gloves off to flip through it and I got the end, he pulled out the real ring and asked for my hand. Of course, I started bawling. I almost got frostbite afterwards because I refused to put my gloves back on!"
The flipbook was designed by US-based artist Ben Zurawski, who goes by the name The Flippist.
You can watch the full flipbook animation below.