Ryn, Ben and Maddie must protect Bristol Cove from Tia’s army. Meanwhile, Ben’s injections are producing unexpected results, which alarms both him and the others. Xander juggles best man duties…

Ryn discovers a refuge of injured mermaids that escaped Tia’s violent takeover. Ben and Xander get caught in a battle with Tia’s troops. Maddie feeds Robb half-truths to secure his…

The team tackles their primary mission: stop a cataclysmic event that could change the course of human history.

When the daughter of a Chinese Triad family disappears, Shawn and Gus take on the case.

Supergirl learns the true depth of Serena’s nefarious plans for Earth. Supergirl, Mon-El and Alura must devise a plan to stop her before Serena gets to Earth. J’onn prepares to…

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.

When multiple children get sick from lead poisoning, Morgan Edge points the finger at Lena and blames her creation of the lead bomb she made to save National City from…

Supergirl challenges Rhea to battle to save National City. Meanwhile, Superman returns and Cat Grant offers Supergirl some sage advice.

Supergirl grapples with whether or not to obey the President’s orders regarding Rhea’s latest actions. Meanwhile, Cat Grant returns to National City.

When an alien attacks National City, Supergirl and the DEO learn the alien is a Phorian, an otherwise peaceful race with telekinetic powers. Guardian gets a lead on the Phorian’s…

With tensions running high at Titans Tower, Kory tries to learn more about Conner, while Dick sets out alone to track down Deathstroke – with a familiar voice haunting him.