Try to figure it out.

Explanation (after you watch):

...

This whole video was shot backward, then reversed to make it look like they were walking forward.

If you watch it again you can see little things that give it away, such as the movement of the girls' hair, the way they walk (especially down/up stairs), always looking behind themselves, how Mike falls, other people walking "backward", the golf cart driving "backward", and when they get in the elevator going from the first floor to the 4th he presses the 1st floor button right before it "opens".

At the end, the whole thing is "reversed" to kind of show you how it actually looked to film.

Cast: Michael McKinney, Jackie Minney, Janelle Cook, Mikey Bradbury, and Jennifer Lundin.

Filmed & Edited by Jake Zander.

Music: Just A Dream (Extended Mix) by Nelly & Dj Steven Papo
remix.vg/nelly-just-a-dream-extended-mix-dj-steven-papo-9036/

This video is also on youtube:
youtube.com/watch?v=zaHB-ZygjPE