Cheri Haight, 22, left, and her sister Jennifer, 19, play the brother and sister in "Ka" at the MGM Grand. They are trained in wushu, an ancient form of Chinese martial arts. Photos by Jeff Scheid. Cheri Haight practices wushu in the workout area in the "Ka" theater at the MGM Grand. Her sister Jennifer looks on. Jennifer Haight, left, and sister Cheri apply makeup before a recent performance. Cheri Haight, left, and her sister Jennifer stretch in preparation for a performance of "Ka." The pageant scene is one of the favorites of sisters Cheri , left, and Jennifer Haight because they get to play. Sisters Jennifer and Cheri Haight prepare for a performance of "Ka." They prepare for the final battle scene of the show. Jennifer, left, plays a princess while Cheri, in green, plays a prince.

When Cheri and Jennifer Haight started taking kung fu lessons 10 years ago, they thought it would lead to self-defense techniques and improved self-confidence.

They never imagined their skills -- especially their mastery of wushu, a stylized version of kung fu -- would lead them to jobs with Cirque du Soleil and roles in one of the Strip's biggest productions.

But that's where Cheri, 23, and sister Jennifer, 20, have been since 2003.

For two shows a night, five nights a week, the slight-framed, gregarious sisters take the stage at MGM Grand as the main characters of the twin brother and sister in "Ka." The story line follows the twins, a prince and princess, after their empire is attacked by would-be conquerors. The two are separated and the show follows them on their journeys as they try to reunite.

Throughout the 90-minute performance, they utilize their wushu skills extensively, fighting against the evil forces that want to keep the brother and sister apart. They leap, kick, jump, masterfully spin wooden staffs and perform other moves, all while acting on a moving stage.

"Wushu is modern form of kung fu made to look pretty," Cheri said.

Originally from San Francisco, the sisters started studying kung fu when Cheri was 13 and Jennifer 10, then decided to focus on wushu "in order to get better at it and become champions," Jennifer said. The two have a younger sister who hasn't been bitten by the wushu bug, yet.

Both became good at it. They've won several national competitions and were members of the USA wushu team from 2001 to 2003.

The sisters were invited to the 2002 Winter Olympics in Salt Lake City to promote wushu as an Olympic sport.

"Unfortunately, it wasn't accepted as an Olympic sport," Cheri said, "because you have to subtract a sport to get one."

Their disappointment was short-lived.

After the demonstration at the Olympics, they received an offer from Cirque du Soleil.

They started with "Ka" as the show was being created.

The competitive aspect of their martial art prepared them to handle the unknown, a good skill to have when performing live theater.

"Martial arts is about learning about yourself, discipline and learning who you are," Cheri said.

Tournaments teach patience and time management, Jennifer said.

Every night, the sisters face pressures while onstage; they must adapt to lighting, cast changes and potential obstacles.

Though their first love is wushu, both sisters have come to enjoy the acting part of their jobs just as much.

"It's really nice working with my sister because we have a really good chemistry," Jennifer said.

There are parts in the show where the two are playing and supposed to seem as though they're having a good time.

"Actually, we really are. Sometimes Cheri will do something that will make me bust out laughing," Jennifer said. "I get to work with my sister, who I'm really close to, so when we get separated (in the story line), it feels like we're really being separated. ... It's fun because you play off real emotions."

Sometimes, the sisters see audience members crying at the end of the show. It's that kind of reaction that keeps them inspired, they agreed.

"It really makes you glad you're an artist and glad you work with 'Ka,' " Jennifer said.