Sean Astin is returning to Supergirl for tonight's episode. The actor guest-starred in an episode before the Crisis on Infinite Earths took place as Kelly's old friend Pete Andrews from the Army. However, Astin's Pete character wasn't who he seemed to be. We later found out that he was actually Malefic, J'onn's evil brother in disguise. Thankfully, Astin's Pete Andrews character gets to be himself this time around, which should keep it interesting for Astin, who is a major fan of the Supergirl TV series. A clip from the episode reveals that Pete is going to be a big help to Kara and Alex.

Sean Astin posted his excitement on social media. "So excited to be back on Supergirl tomorrow night... and I'm a linguist!!!" In a clip from tonight's episode of Supergirl, Kara (Melissa Benoist) and Alex (Chyler Leigh) visit Pete Andrews at the United States Congressional Library "because they need his help tracking a symbol related to Leviathan." Astin's Pete character seems to know a lot about what he's talking about in the brief clip from the upcoming episode.

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As it turns out, Sean Astin isn't the only fan of the show in his household. He and his daughter are both massive fans of Supergirl. "He's seen every episode. So he cares so much and was so kind and excited and lovely," says Kelly Olsen actress Azie Tesfai. She went on to say that working with Astin has been her favorite part about working on The CW series thus far. When the actor showed up in the fall 2019, he had a much different story arc for his "Pete" character. "He is such a kind person, so to see him play this character that ends up being so dark is so interesting because he's so likable as the character Pete and as himself."

Supergirl Season 5 has also featured Brainiac 5 (Jesse Rath) who set up an alliance with Lex Luthor (Jon Cryer) in order to defeat the Leviathan. It will be interesting to see how Sean Astin's knowledge of the Leviathan brings everything together. Rath recently spoke about what DC fans can expect in the next few episodes and it sounds pretty intense. Rath had this to say.

"...In terms of what's to come in these next two episodes, I'm not saying you should expect a bunch of Brainy cycling through a bunch of personalities, but things get just as intense and emotions are high and the situation is very dangerous. There are some epic scenes to come, and I think you'll be happy with it and I'm very excited for everyone to see. I'm very excited to it see myself!"

Sean Astin recently appeared on Josh Gad's virtual reunion of The Goonies. The whole cast joined the Frozen actor to answer questions and talk to each other about what it was like working on the set so long ago. As far as virtual reunions go, Gad was able to create quite possibly the best one we've so far, and even convinced Richard Donner and Steven Spielberg to participate. As for tonight's episode of Supergirl, you can watch the clip above, thanks to Entertainment Weekly.