Myr’nn inadvertently causes psychic disturbances at the DEO; Supergirl must work with J’onn to contain the chaos; Mon-El begins training Kara in fighting techniques he’s learned in the future.

Lexa and Clarke get into a heated discussion during battle preparations; Bellamy races against time.

Clarke is faced with a difficult choice and Raven helps Bellamy navigate Mount Weather as Dr. Tsing begins to harvest the 47, while Jaha and Murphy encounter a stranger on…