As Alan risks killing Peter in a desperate effort to cure him, Walker teams with a mysterious young researcher to survive their quarantine. Jordan discovers her Rapid Response test is flawed.

As Alan's controversial cure leaves Peter clinging to life, the unchecked virus forces Jordan to make a devastating decision. Walker discovers the surprising truth about her new ally, while Daniel squares off against Balleseros.

After Daniel leaves Balleseros to die, the mystery surrounding his connection to Hatake is revealed. As he works to save Peter, Alan struggles with his feelings for both Walker and Jordan.