4x16: Tongues of Men (2)
4x15: Tongues of Men (1)
4x14: The Red Planet
4x11: The Wolf Equation
4x10: The Human Animal
4x09: The Gene Engineers
4x08: The Pill for the People
4x07: Bye Bye Blackbird
4x05: The Plastic Prison
4x04: The Sunspot Mystery
4x03: What Price Coal?
4x01: Hitler's Secret Weapon
3x19: The Genetic Chance
3x18: Inside the Shark
3x17: Death of a Disease