A first-time viewer reacts to Sheldon's competitive streak, a full-size time machine purchase, and the arrival of his twin ...

Johnny Galecki, Kunal Nayyar, Summer Glau, Simon Helberg and Jim Parsons in The Big Bang Theory. "Mark Hamill was pretty ...

Between both the original series and Young Sheldon, one Sheldon line still stands out as The Big Bang Theory antihero's ...

TVLine is keeping a running list of every actor from The Big Bang Theory, Young Sheldon and Georgie & Mandy who appears in ...