The Pennsylvania Ballet performed an endearing program called "Revolution" at the Merriam Theater on Thursday, beginning this weekend's run. It ended with a world premiere, the challenging Chicken Bone Brain by Brian Sanders, Philly's favorite prankster of dance.

A company premiere by British choreographer David Dawson (2010's The Third Light) opened between two angled black-and-white walls by John Otto creating an alluringly mysterious third light. In Gavin Bryars' sustained-tempo score, violinist Luigi Mazzocchi softly supported the mercurial choreography. In varied groupings, 10 men and women in Yumiko Takeshima's violet costumes executed short lunges ending with spines arched backward and one leg extended in an ostrich step.

Two simultaneous nonsymmetrical duets centered the work. The five men lined up as though at the barre, arms and back muscles rippling. A tensile Sterling Baca perfectly matched the pliant and plaintive ballerina, Oksana Maslova, with many lovely images in their lifts, some with her legs abruptly diamond-shaped. He reluctantly drew his hand from hers and her chin fell to her collarbone, shoulders hunched, as he left her alone. Dawson ended this sensually enigmatic dance with all facing us, swaying arms lyrically. We became their mirror at the barre.

At first, the middle piece, George Balanchine's 1957 Square Dance, looked a bit limp. It comes from an era when ballerinas smiled, even if their pointe shoes pinched, and raised their arms for applause at the end of a sequence. Amy Aldridge and Alexander Peters shone as the principal dancers in white while the other dozen dancers in powder blue displayed the partnering and fancy footwork of the time. Aldridge dazzled with her scissoring feet. The formations, prancing feet, and kicking heels near the end were the few suggestions of an American square dance.

Pedro Silva, Sanders' longtime collaborator, designed Chicken Bone Brain's clever set of gigantic chicken bones lighted by Terry Smith. Sanders took the title from a line in the '70s song "Look What They've Done to My Song, Ma" by Melanie. All dancers want to take to the air, and Sanders gave these ballet dancers the first opportunity. But Sanders is no ordinary aerialist. He makes them dance for it. Baca, Jermel Johnson, and Arián Molina Soca floated and pulled themselves along the bones as though born to it, although they did take some additional training for these feats.

Known worldwide for his dramatic openings, Sanders did not skimp here. Taking an atmospheric tone from Denise Levertov's poem "Suspended," a lone figure bathed in bloodred light appeared through the curtains, torso bent forward and fists pumping, as though walking on a treadmill - thrilling and revolutionary for this company.

Additional performances: 2 and 8 p.m. Saturday and 2 p.m. Sunday at the Merriam Theater, 250 S. Broad St. Tickets: $35-$135. Information: 215-893-1999 or