THE BEAST WITHIN — Lives are at risk as Clarke (Eliza Taylor) and Lexa (guest star Alycia Debnam Carey) encounter a new enemy. Bellamy (Bob Morley) and Lincoln (Ricky Whittle) agree to work together to break into Mount Weather. Murphy (guest star Richard Harmon) helps Jaha (Isaiah Washington) confront his past. Meanwhile, Indra (guest star Adina Porter) makes Octavia (Marie Avgeropoulos) an offer she can’t refuse. Paige Turco and Henry Ian Cusick also star. Dean White directed the episode written by Akela Cooper (#210). Original airdate 1/28/2014.