Watch The 100 season 3 finale online: Can Clarke defeat Alie?

The 100 season 3 returns with its finale episode this Thursday, where Clarke Griffin will enter the City of Light to take down Alie once and for all. Episode 16 is titled, Perverse Instantiation - Part Two, which will air on 19 May at 9pm EST on The CW.

The official synopsis reads as follows:

Click here to watch the episode online on The CW website (only in the US).

A promo for the episode opens with Pike telling Bellamy, Octavia, "If we are going to survive this, we need to stand together!" Then we see Clarke figuring out a way to stop Alie and adding, "I have to go inside the City of Light".

While Clarke runs into familiar faces in the City of Light, Bellamy, Pike, and the rest of the team are entrusted with the job of keeping Clarke's body safe, as Murphy points out, "It doesn't work if she dies."

Clarke will run into Lexa, who died tragically in episode 7, inside the City of Light. Eliza Taylor [who plays Clarke] spoke to TV Line about Clarke and Lexa's reunion and said, "I think people have seen photos online and know already that Alycia [Debnam Carey] is coming back for the season finale. It's just a matter of how and in what capacity. Shooting downtown in Vancouver, there was no way we weren't going to get found out. So I can't say anything about how it happens or how much we see of her, but I think people are going to be happy."

Do not miss Clarke and Lexa's reunion in The 100 season 3 finale episode airing this Thursday on The CW.