The past comes back to haunt both Oliver and Laurel. Curtis is upset when he discovers that Diggle and Lyla have restarted The Ghost Initiative with Diaz, China White, Kane…

Jaha makes a surprising move. Clarke gets help from an unexpected source. Lincoln seeks revenge.

Wick and Raven are faced with a setback. Maya and Jasper witness a terrible act.

Kane takes part in a mission to make peace with the Grounders. Jasper decides to take part in a risky experiment. Lincoln enters a world of pain and President Dante…

Clarke ends up being betrayed by somebody that she trusted. Bellamy, Finn and Murphy attempt to save a stranger.

After discovering a horrifying project in Mount Weather’s medical ward, Clarke joins forces with an unexpected ally.

Clarke wants answers from the President. Abby performs emergency surgery. Octavia will do anything to find Lincoln.

Clarke is still on her own in the white room, frantically attempting to make sense of her bizarre surroundings. Lincoln and Octavia’s plan is ruined and an enemy returns.

As the remaining members of the 100 face off against the Grounders, Jaha makes a noble sacrifice to ensure the Ark makes it to Earth.

Shumway secretly orders one of the 100 to kill Bellamy. Meanwhile, hallucinogenic nuts provide Octavia with an opportunity to help the Grounder escape the camp, and Bellamy and Clarke investigate…

While Bellamy tortures the Grounder, Raven and Clarke make contact with the Ark and ask Abby to help them save Finn. On the Ark, Kane deals with his guilt, and…

Bellamy, Finn and Jasper head into Grounder territory to search for Octavia, as flashbacks show the siblings’ difficult childhood on the Ark. Meanwhile, Raven finds out about Clarke and Finn.

Sam and Dean are stunned when a man who claims to be Henry Winchester, their grandfather, suddenly appears in their hotel room demanding to know where he can find John…