Krypton may have exploded, but why should that mean that Supergirl and her cousin are the only Kryptonians left? Let’s meet a whole space colony of them!

Previously, on SUPERGIRL

When Kara and Mon-El decided to go out into space in search of the Black Rock of Yuda Kal – a piece of Krypton that Lena Luthor hopes to reverse engineer in order to drive Reign out of Samantha Arias’ body – they were certainly not expecting to find a much larger piece o Krypton floating in space…

Instead of finding a meteorite or asteroid or something smaller, the pair come across a city floating in space where the black rock can be found. And of course, this floating city is Argo City, one of Krypton’s largest cities and, now, the largest and last remaining compound containing Kryptonian life. Before this discovery, that honor went to Earth, with Superman, Supergirl and several Kryptonian prisoners at Fort Rozz.

And who should come across Kara and Mon-El as they look for the black rock? Of course, it’s Kara’s mother Alura, who we all thought died when Krypton exploded all those years ago. Time for a family reunion!

Alura, of course, is portrayed by Erica Durance, who starred in the latter seasons of SMALLVILLE as one of the best Lois Lanes ever, and she is overjoyed to find out that her daughter is still alive. She thought Kara was lost when her pod was knocked off course and ended up in the Phantom Zone, allowing her younger cousin Kal-El to arrive on Earth first and grow up to be… SUPERMAN… before Kara even made it to the planet. This has all been helpfully laid out in the opening monologue for anyone who may need to catch up.

Argo City, of course, survived because Kara’s father, Zor-El, covered the city in a protective shell. With everyone floating in space, the only reason everyone is still alive is through the help of the Black Rock of Yuda Kal. Which means that removing any of it means that death will come for the people of Argo City that much faster. That throws a bit of a monkey wrench in Supergirl’s plan to bring some of the rock back to Earth.

Never fear, though, Alura promises that Kara will get a chance to make her case with the council, who want to leave much of the history and traditions of Krytpon far behind them. They also want to live as long as possible, so many members of the council are opposed to giving Kara any of the black rock.

The final vote comes down to a council member named Selena… who is also the Dark Kryptonian prophet who has been guiding Reign and the other Worldkillers in their quest for “justice” on Earth. Of course Selena is going to say no, right? It can all be part of her plan! Selena surprisingly – or maybe not surprisingly… who knows any more – Selena votes to give Kara some of the Yuda Kal black rock, breaking the tie. Now, Kara and Mon-El can go back to Earth and give Lena the rock so she can get to work. And it’s just in time, too, as Reign escapes her prison.

Meanwhile, on Earth, someone is trying to kill Alex, who is concerned about what happens to Samantha’s daughter Ruby if Alex is killed while taking care of Ruby. But the would-be killer is pretty incompetent and gets caught despite being an alien with supernatural abilities. And Winn finally gets some purpose, as Alex tasks him with watching Ruby. At first, he’s a jerk about it and then realizes he was a jerk and decides to be a better babysitter. Compared to the main story with Kara on Argo City, nothing else really mattered to me here.

With Reign out of her prison and Lena in possession of the Black Rock of Yuda Kal, the next episode could be pretty explosive.