In the fourth season premiere Echoes, Clarke (Eliza Taylor) and her friends struggle with how to proceed after the fate of the world is revealed.
Paige Turco, Bob Morley, Marie Avgeropoulos, Devon Bostick, Lindsey Morgan, Christopher Larkin, Richard Harmon, Zach McGowan, Isaiah Washington and Henry Ian Cusick also star.
Dean White directed the episode written by Jason Rothenberg.
Series: The 100 Season 4 Episode 1
Airdate: Wednesday 1 February 2017 at 9.00pm on The CW