What do you do when you are in the museum at night on Counterfeit Island?

Entering the museum through the Dragon Face hatch, you have three things to do.

1) Slip past the window so the Security Room guard doesn't see you

2) Hide behind the lasers in the Statue exhibit, avoid the lasers, and exit right

3) Climb up the light above the painting of "The Scream"

This may not work out well, but it is the way the quest has to be played.