When "Supergirl" took it's mid-season break Lena Luthor helped stop Project Medusa, Lillian Luthor was turned over to the authorities, Jeremiah Danvers was found alive and a prisoner of Cadmus, and aliens were hunting for Mon-El.
This new extended teaser shows Brit Morgan returning as Livewire, more of Mon-El's training and the return of certain alien foes.
CW's description for the January 23 episode "Supergirl Lives", directed by hyper-kinetic fan boy Kevin Smith, says:
Kara (Melissa Benoist) is moved by the story of a missing woman named Izzy (guest star Harley Quinn Smith) and decides to investigate despite Snapper Carr's (guest star Ian Gomez) order to leave it alone. Kara takes Mon-El (Chris Wood) with her to the last place Izzy was seen and the duo find themselves thrust through a portal to another planet, Slaver's Moon, where the downtrodden are sold as slaves. The leader of the trafficking ring is none other than Roulette (guest star Dichen Lachman).
To make matters worse, Slaver's Moon has a red sun, which means Kara and Mon-El are stripped of their powers and stuck on the planet with no way home.
Meanwhile, back on Earth, Alex (Chyler Leigh) blames herself for Kara's disappearance, fearing she's become too focused on her new relationship with Maggie (guest star Floriana Lima) and too complacent in watching out for her sister.
"Supergirl", starring Melissa Benoist, David Harewood, Jeremy Jordan and Chris Wood, returns on Monday, January 23. Check local listings for exact times and channels.