Morgan believes that a recent attempt on his life was made by Lena. When Lena is poisoned, Kara steps in to find out who is responsible for the escalation in hosility. Meanwhile, Sam turns to Alex for help determining the cause of her blackouts.

After Winslow dies, his wife Mary comes to National City to attempt to reunite with Winn. However, a new murderous toymaker threatens Winn and Mary, Meanwhile, M'yrnn asks Alex to keep a secret from Hank, and Mon-El tries to find the right time to tell Supergirl something important about one of the Worldkillers.