Ephraim (Corey Stoll) and Dutch (Ruta Gedmintas) team up to bring down one of the most powerful ally of the Master in the upcoming episode of FX's horror drama series "The Strain."

In "The Assassin," TV Guide reports that the two will find themselves pitting against a dangerous foe sent by the Master in his continued quest to take over the city. While his friends are busy with keeping the citizens alive, Abraham (David Bradley) will search for the true owner of the Lumen. Meanwhile, Feraldo (Samantha Mathis) will get into trouble with the Mayor, perhaps due to her abrupt exit from their important meeting last time.

Last episode, viewers saw a horde of vampires, led by Eichorst (Richard Sammel) and Kelly (Natalie Brown), creeping into the city. Their "private party" arrived by boat. Eichorst's plan to kill the power of the entire area and render the ultraviolet (UV) light useless was a brilliant one. For a while, it appeared to be working, as the undead could freely move around for the kill.

The fighters split up to cover as much ground possible. Eph, Nora (Mia Maestro), Fet (Kevin Durand), and Zach (Max Charles) decided to go to the power plant to bring back the UV lights. Abraham, on the other hand, went back home, where he knew Eichorst was waiting for him. Realizing that the vampires outnumbered the fighters, Feraldo rallied the civilians together in a "fight or die" battle.

In this episode, the Master's minions took a direct hit. Not only did the UV lights that Nora repaired decimate the vampires, but Kelly and Eichorst also got seriously hurt. Fet and some police officers shot Eph's estranged wife, while Abraham and Eph fatally wounded Eichorst. Both, however, managed to escape. The entire city celebrated the defeat of the vampire forces, but the crew knew that it was not the end.

"The Strain" airs Sundays at 10 p.m. EST on FX.