Kara comes face to face with a Bizarro-doppelgänger of her, who was brought to life by Maxwell through a combination of genetics from her DNA and a comatose victim; the double is programmed to destroy Supergirl. Kara on the other hand, believes that Maxwell is the one the DEO should go after when she realizes he knows her secret by sending Bizarro out to kill her. Alex and Hank come up with a plan to keep Maxwell from exposing Kara while countering Bizarro with blue kryptonite. Meanwhile, Kara starts to get to know Adam but is not sure where to take the next step. A mysterious plant attacks Kara.