Dr. Walter Bishop

Walter Bishop is a brilliant, formerly institutionalized scientist sprung from a mental hospital because the FBI needs his expertise in fringe science. Released into the reluctant custody of his estranged son Peter, he's giddy, tangential, and unnervingly cheerful, prone to non sequiturs about cows and root beer floats even as he examines horrifying phenomena with real expertise.

John Noble plays genius and fragility as the same note rather than alternating between them, so Walter's whimsy never feels like comic relief bolted onto a drama — it feels like a mind that has been broken and rebuilt slightly wrong. The show lets him be funny and unsettling in the same sentence, and Noble never tips his hand about which is coming.