'Supergirl' Season 5 Finale: Kara and Lena team up against Lex and Leviathan, but can Lena be trusted?

'Supergirl' might be ending sooner than what was planned, but it's not going to go off without some fireworks. Throughout the season, Lena Luthor (Katie McGrath) has been giving ex-BFF Kara (Melissa Benoist) a cold shoulder, because she didn't tell her that she was Supergirl. Lena joined hands with a recently-resurrected Lex Luthor (Jon Cryer), who wants to pit the Leviathan against Kara.
Of course, she refuses to see that Lex is manipulating her against Kara. But hey, looks like things might finally change for the former besties and they will join hands and save the day...or not, or at least try to. At least, that's what the synopsis for the finale suggests. Cryer has given several hints in interviews hinting that Lex might just win this round, as we saw him defeated in Season 4.
The synopsis for the 'Supergirl' Season 5 finale reads, "Supergirl (Melissa Benoist) realizes that in order to stop Lex (guest star Jon Cryer) and Leviathan she must work with the one person she never thought she’d trust again – Lena (Katie McGrath). Nia (Nicole Maines) keeps dreaming about Brainy (Jesse Rath) but struggles with what the dreams are trying to tell her. Meanwhile, Brainy realizes there is only one way to stop Lex."
Well, yikes.
Yet, Lena is Lena and considering she is so filled with hatred for Kara, it remains to be seen whether she will be an ally or betray Kara again. Lex has been brainwashing her consistently against Kara. However, this might just be the moment Supercorp fans were waiting for---to see a reconciliation between Lena and Kara.
Apart from that, we are going to see Brainy's (Jesse Rath) female doppelganger back in action, played by the actor's sister, Meaghan Rath. "Well, in [episode] 19, my sister comes back to the show," Jesse told CBR.
"She will return to the show. So I have a handful of scenes with female Brainy, or Meaghan Rath, or whatever you want to call her. So I'm very excited to see those scenes. I always love working with my sister and I'm very grateful for her to come and do the show, so I can't wait to see those scenes."
Tune into 'Supergirl' on Sundays at 9 pm.