There are many reasons to celebrate BalletX's summer series, which opened Wednesday night at the Wilma Theater: three world premieres and live music for two pieces. Two new dancers (Stanley Glover and Anna Peabody) joined the company, and these are the final Philadelphia performances for two others (Daniel Mayo and Gary W. Jeter II).

Three new works in an evening doesn't always add up to a cohesive program, but this series had a little for everyone: ballet in Andrew McNicol's Requiem, contemporary with a playful edge in Matthew Neenan's Situated, and musical theater in Penny Saunders' Rock-a-Bye.

Also, unusual for BalletX, the women danced en pointe in all three pieces.

Saunders' piece is the reason to see this program. Rosie Langabeer — who in 2014 created original music for Neenan's Sunset o639 Hours, the company's biggest triumph — scored Rock-a-Bye. They worked in collaboration; Langabeer composed while Saunders choreographed. Langabeer, Tara Middleton, and Gregg Mervine sing and play a number of instruments onstage behind the dancers, and the music is wonderful on its own. (Langabeer and the BalletX Players played a WXPN Key Studio Session earlier this week.)

Rock-a-Bye, set in a kitchen, is about mothers and children. The story is a little loose. But the movement more than makes up for it, opening with Caili Quan dancing in front of the curtain, while numerous hands — presumably those of her children — poke out from beneath it, shades of Pippin's stagehands.

McNicol is this year's BalletX choreographic fellow, and he was paired up with Neenan as his mentor. The fellows are dance makers on the rise, although McNicol has already created work for the Royal Ballet, the London Olympics, and the New York Choreographic Institute, and also has a new company of his own.

He chose to present a ballet to Mozart's Requiem — a piece that's been used in ballet many times. But his result was a more fully formed work than some of the fellows produced, with dancers often moving as though one organism, stretching, pulling, living, and dying. At times, the movement was a bit busy, particularly when McNicol tried to highlight a solo or duet among the group.

His mentor, Neenan, followed up with Situated, a work with his usual witty eye. The Mendelssohn score, Songs Without Words, was gorgeously played live at the side of the stage by Pennsylvania Ballet principal pianist Martha Koeneman. The dancers, in colorful sweat suits, danced on, under, and around chairs, speaking phrases in various languages as they assemble the chairs into a large sort of Jenga puzzle, picking out pieces one at a time to create feats of balance that resemble their own gravity defiance.