The Pawn Stars make calculated moves when some handwritten math by Albert Einstein could multiply their profits. Chumlee tries to prove he isn't dim when he pays big bucks to have an antique headlamp tester shining brightly once again. Corey and Chumlee take a stab at buying a prop from the classic horror movie "Child's Play." Later, a pill case pops into the shop that may have once belonged to Hollywood legend Carole Lombard, but Rick does a second take to make sure it's not a stand-in.