Watch 'ghost' dancers appear out of nowhere in stunning 'SYTYCD' routine

In theater, so-called ghost lights are used to illuminate empty, otherwise dark theaters so people don't trip. Also, those lone bulbs are there to make way for ghosts.

Choreographer Travis Wall decided to harness the superstition around the ghost light for a piece on So You Think You Can Dance performed by his group of stage dancers left in the Top 18 Monday (excluding Derek, who was injured).

And the results are stunning.

The Ghost piece was intended for TV, so Wall choreographed the entire routine with a Steadicam in mind. The camera angles and lights make it look as though dancers pop in and out of frame by magic.

After the show, Wall talked to Paste BN about how he put together what will probably be an Emmy-nominated piece.
"I've had this idea over a couple of months," when I found out I'd be coaching the team of stage dancers, he said. "What's to do with a stage? I thought about Broadway, then I thought about having spotlights, and then I thought there's a ghost light they put on in theater."
Wall, who has been planning this piece since April, didn't actually put together the steps until he was with his dancers. He choreographed with the group for about six hours, he said. This morning, he told the camera operator where to shoot.
"Everybody came together: hair, wardrobe, makeup and the lighting designer who personally designed the lights," he said. "I'm really happy with it."