This is the first time that LaMonica Garrett is credited in the main cast. (In his previous appearances, he's listed as a guest star.) He is also credited whenever he appears on Arrow (2012) Season 8 or The Flash (2014) Season 6.
In 79 AD, the city of Pompeii, south of Rome, was destroyed by Mount Vesuvius and buried under 4 to 6 m (13 to 20 ft) of volcanic ash.
The episode title "The Wrath of Rama Khan" is a nod to that of Star Trek II: The Wrath of Khan (1982).
Fans have started to wonder if the friendship between the two women has any chance of being saved. According to Katie McGrath, she thinks it's possible, largely because Lena does genuinely care about Kara. "I think there's always potential, you know?" McGrath told TV Guide. "I think the writers are very smart, and I think they have a very clear, articulated plan about what they're doing. And I would hate to think that you're not going to get Kara and Lena back as they were before. And I think fundamentally Lena is still a very good person, and I think she does just miss her friends. She misses Kara desperately, and part of me believes that Lena would do anything to get that back if it meant that Kara wouldn't, as she thought, betray her again. If Lena felt that Kara couldn't betray her again, I think Lena would do anything to get that friendship back. I think the illustration of that is how hurt she was. You couldn't feel that amount of hurt if you didn't actually care." While a reconciliation between Kara and Lena is something that fans will have to wait to see to play out on Supergirl - if it happens at all - Lena's fraught relationship with Kara isn't going to prevent Lena from being involved in the upcoming fight for the Multiverse in "Crisis on Infinite Earths." During the Supergirl hour of the crossover, J'onn and Alex will ask for Lena's help in trying to save Earth-38 and McGrath is excited to be part of the crossover. "It's been kind of nice because every year I'm never involved, and I've always felt a bit left out because it's always such a huge thing and a big deal and kind of very special because obviously so much of everything leads up to it," McGrath said.