In the next episode of "Supergirl," Kara Danvers a.k.a. Supergirl (Melissa Benoist) comes face-to-face with the villainous Reign a.k.a. Samantha Arias (Odette Annable).

The trailer for the upcoming installment titled "Reign" was just recently released and showed Supergirl in a remote field with local authorities investigating a mysterious artifact. Apparently, the symbol from the unknown object has been popping up all over National City. The symbol's origins can be traced back to ancient prophecy which states that it is the mark of the World Killer, Reign. It seems that the ordinary mom Arias will finally transform into the evil Reign and wreak havoc on the city. However, it is against Arias' will because the spirit of Reign appears stronger and overpowers her good side without effort. Supergirl meets Reign for the first time and challenges her, "Take your best shot!"

Meanwhile, tension between Lena Luthor (Katie McGrath) and Morgan Edge (Adrian Pasdar) continues to build. Edge has threatened Luthor's life in the past but was able to get away with it. This prompts James Olsen (Mechad Brooks) to step in and offer Luthor some protection against the treacherous Edge. It seems that Olsen will take on his Guardian persona to protect her. Winn Schott (Jeremy Jordan) will likely be there as well to serve as backup. It remains to be seen what will come of the battle between Supergirl and Reign and if Guardian will be able to protect Luthor.

In the last episode, Kara and her sister Alex (Chyler Leigh) went to Earth 1 to attend Barry Allen a.k.a. The Flash (Grant Gustin) and Iris West's (Candice Patton) wedding which was sadly crashed by Earth-X villains. Nevertheless, the heroes were able to defeat them in the end.

"Supergirl" season 3 episode 9 will air on Monday, Dec. 4 at 9 p.m. EST on The CW.