Sean Astin returns to Supergirl in exclusive sneak peek

The real Pete Andrews is finally ready to stand up on Supergirl.

EW is exclusively debuting a sneak peek from this Sunday's episode that reveals Sean Astin's return appearance on The CW super-series. In case you forgot, the Lord of the Rings actor guest-starred in the pre-"Crisis on Infinite Earths" part of the season as Kelly's (Azie Tesfai) old army buddy Pete — except when we met him then, he was actually J'onn's (David Harewood) evil brother Malefic (Phil LaMarr) in disguise. This time around, there's no shape-shifting shenanigans going on. This Pete is the real deal.

In the clip above, Kara (Melissa Benoist) and Alex (Chyler Leigh) visit Pete, who is a linguistics expert, visit the United States Congressional Library because they need his help tracking a symbol related to Leviathan. To their surprise, Pete's discerning ear helps him pick up on the fact that Kara might be from around here because of the way she talks and writes. Furthermore, it also turns out that he's actually heard "whispers" about Leviathan, so this guy definitely knows his stuff.

Astin initially agreed to appear on the show earlier in the season because both he and his daughter are fans of the show. "He’s seen every episode. So he cares so much and was so kind and excited and lovely," Azie Tesfai told EW in October. "It was the best day of work I’ve had on this show by far. We got to do stunts and all of these crazy, cool things. 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."

Watch the clip above.

Supergirl airs Sundays at 9 p.m. on The CW.

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