The 100 Season 2 Episode 15 Photos Blood Must Have Blood, Part One : ONE STEP FORWARD, TWO STEPS BACK — Clarke (Eliza Taylor) and Lexa (guest star Alycia Debnam Carey) prepare for battle, while Raven (Lindsey Morgan) and Wick (guest star Steve Talley) experience a major setback. Meanwhile, Octavia (Marie Avgeropoulos) and Lincoln (Ricky Whittle) are each forced to make a difficult decision. At Mount Weather, Jasper (Devon Bostick) and Maya (guest star Eve Harlow) witness a horrible act, Bellamy (Bob Morley) follows through on a promise and Cage (guest star Johnny Whitworth) goes public with powerful information. Paige Turco, Isaiah Washington, Henry Ian Cusick and Chris Larkin also star. Omar Madha directed the episode written by Aaron Ginsburg & Wade McIntyre (#215). Original air date 3/4/2015.