You've stealthily descended into the darkness of a vampire cave, setting a sequence of mirrors as you go. When the sun reaches the right angle in the sky, a beam of light will ricochet along the mirrors, strike a diffuser, and illuminate the great chamber where the vampires sleep. Can you place the diffuser correctly and flood the lair with sunlight? Dan Finkel shows how. [Directed by Artrake Studio, narrated by Addison Anderson, music by Saso Puckovski].