Plank

Plank is an option in Stealing the Diamond in the "Undetected Way"/"Unseen Burglar" pathway.

After Henry makes his way to the back of the museum with the Tunisian Diamond, he uses the plank to launch himself across the room.

He lands safely on a cushion next to the back door, and sneaks out without guards Ted McAdams and Jacob Rose noticing him. This results in a success.