The Big Bang Theory - 11x13 - The Solo Oscillation 2018-01-11 Comedy / Romance Jim Parsons - Sheldon Cooper , Johnny Galecki - Leonard Hofstadter , Kaley Cuoco - Penny When Sheldon kicks Amy out to work solo, she and Leonard bond during a series of science experiments. Also, Bert the geologist replaces Wolowitz in the band Footprints on the Moon, and Sheldon finds Penny a surprising source of scientific inspiration. 25 TV-14