Season 4

20 Episodes

Season 4

Episodes

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  • 20 episodes
    20 episodes
    • s4e20The Green Machine
      January 11, 1978
    • s4e19The New Healers
      June 29, 1977
    • s4e18Across the Silent Barrier
      June 22, 1977
    • s4e17Linus Pauling: Crusading Scientist
      June 1, 1977
    • s4e16Tongues of Men (2)
      May 18, 1977
    • s4e15Tongues of Men (1)
      May 11, 1977
    • s4e14The Red Planet
      April 27, 1977
    • s4e13The Business of Extinction
      April 20, 1977
    • s4e12The Dawn of the Solar Age
      April 20, 1977
    • s4e11The Wolf Equation
      March 30, 1977
    • s4e10The Human Animal
      March 23, 1977
    • s4e9The Gene Engineers
      March 16, 1977
    • s4e8The Pill for the People
      March 9, 1977
    • s4e7Bye Bye Blackbird
      March 2, 1977
    • s4e6Incident at Brown's Ferry
      February 23, 1977
    • s4e5The Plastic Prison
      February 9, 1977
    • s4e4The Sunspot Mystery
      February 2, 1977
    • s4e3What Price Coal?
      January 19, 1977
    • s4e2The Hot Blooded Dinosaurs
      January 12, 1977
    • s4e1Hitler's Secret Weapon
      January 5, 1977