It is the plague year of 1666. Isaac has been sent home from his doctoral studies at Trinity College Cambridge back to his mother in Woolsthorpe Manor. Rainbows, prisms, and reason have been his sole companions. He has not set foot outside in quite some time, but he is making significant progress toward confirming the Corpuscular Theory of light. All he needs to do is finish this morning's experiment. It will surely present no challenge at all to a determined man of science.