In a world being driven apart for political gain, choreographer Mark Haim wanted to make something joyous and humorous that brings people together.

He asked 432 people from more than 20 countries for a video of them doing 5 to 10 seconds of movement. He chose dancers, students, friends, and relatives, some of whom he hadn't spoken to in years. The idea was to learn all their "dances" and perform them from oldest to youngest, becoming a single vessel for hundreds of different people.

Haim stipulated some rules. He had to be able to talk to each person on the telephone. He wanted to have as wide a variety of ages, races, and genders as he could. He wanted to get affirmative consent from everyone, which ended up being a little difficult with the 1-year-old. "I had to sit down with Harvey [the 1-year-old] at a rehearsal and ask him if he wanted to do this thing, and he nodded his head cluelessly," Haim said, laughing, at a recent rehearsal.

In the end, 371 people sent in videos. "I was grateful that not everybody sent them because nobody only sent me five seconds—the average was 15."

Haim's younger sister gave him a playful dance that cracks him up every time. His parents, who were married for 29 years, both sent him movements that involved eating: His Italian father sent a video of him chewing a basil leaf and then dismissing the camera in a "fuhgeddaboudit" gesture; his mom did a quirky jive before plopping a piece of bread on her tongue.

There's a stuffed cat in the show because Haim's high school best friend's wife sent in a video of her petting her cat on a sofa. At one point, Haim licks water out of a dog bowl because he and his high school friend used to do that for fun when they were kids. One of his friends was getting a knee replacement just before he called them, so they gave him a move with crutches. His friend Pam did a dance in high heels and a parka, so he'll wear those items at some point, too.

The dance has taken more than two years to learn. When he had memorized 150 of the movements, he thought to himself: "There's no way I'm going to memorize 371." But, he added, "Yesterday I ran through 230 of them. It's been this amazing research into memory, how memory works, how much we can hold."

Though everyone sent in different kinds of dances—one accomplished modern dancer sent in a flurry of complex movements requiring Haim to twist, leap, toss up an arabesque, and fall gracefully to the floor—Haim noticed a pattern of curvilinear movement connecting them all. He also noticed that the older people and the younger people moved very similarly. Both observations reinforce the idea of the circular nature of time.

The show is called Parts to a Sum. It premieres on April 5 at Velocity and runs through April 13. After his dance, the bar will open up and a postshow party will begin. Haim will play the sequence of video submissions on a big screen so the audience can see the hundreds of parts that made up his joyful sum.