Blaine - in his new identity as Nightbird - calls to order the first Society of Superheroes meeting. The McKinley kids are dressed as their own crusading creations: Asian Persuasion (Tina), Blonde Chameleon (Sam), Tarantula Head (Joe), Sweet 'N' Spicy (Sugar), Queen Bee (Becky), The Human Brain (Brittany) and the very Professor X-like Dr. Y (Artie). Blaine ignores Tina's prodding to contact Kurt and reports that the glee club's Nationals trophy has been stolen, replaced with a laptop message from a mystery man among the Dalton Academy Warblers.
Jake asks Marley out but is rebuffed by Ryder, who already has a date with her and warns that he won't let Jake hurt her. Tempers flare, but Finn breaks up their scuffle. Ryder and Kitty join the glee club, qualifying it to compete in next week's Sectionals. Finn grasps at straws for a theme - singing Foreigner songs in foreign languages while wearing foreign wardrobe - but the students aren't impressed.
As the SoS's advisor, Coach Beiste gets into character as The Beiste-master and suggests Finn try it himself: "Clark Kent was a great guy, but it was Superman who inspired them." Meanwhile, Sebastian leads Blaine to the Warblers' new mastermind: Hunter Clarington (Nolan Gerard Funk), a former military academy champion choir leader recruited by Dalton. The trophy was bait: Hunter plays on Blaine's feelings of alienation from New Directions and his desire to escape painful memories of Kurt to lure him back to the Warblers. Against the backdrop of Kelly Clarkson's "Dark Side," Blaine is seen slipping back into his blazer, feeling tempted.
Finn becomes The Almighty Treble Clef, "uniter of glee clubs." With simmering archrivalries threatening the club's harmony, Finn uses an Avengers analogy: powerful individuals are even more effective as a team. For the new "Dynamic Duets" theme, he pairs enemies Jake and Ryder and Marley and Kitty as duet partners.
As tensions rise between Ryder and Jake, both assume the identity of Mega Stud, playing their rivalry out to R.E.M.'s "Superman." After a full-on brawl, Finn enforces "the Kryptonite Lesson": each must confess his deepest fear to the other, in hopes of recognizing their greatest strengths. Meanwhile, Blaine confesses that, with hopes of dousing his brokenhearted feelings, returning to the Warblers may be "my birthright and my destiny."
Marley's ongoing issues with her body image - she's still experimenting with bulimia - and the possibility of a spandex costume scare her, but Kitty promises to be supportive. In the weight room, Jake passes Ryder a note detailing his secret fear, but Ryder insists that Jake be a man and reveal it to his face. Jake admits that he feels like he doesn't fit in anywhere because of his mixed-race background, and McKinley students like Phil Lipoff never cease to reinforce this. Ryder confesses that the reason he made Jake tell him aloud was that he can't read the note Jake passed.
After bolstering Marley's confidence in her outfit as Wall Flower, Kitty - wearing a skin-tight catsuit and cracking a whip as Femme Fatale - kicks off Bonnie Tyler's "Holding Out for a Hero," joined by Marley's revised persona: Woman Fierce. By the duet's end, the students realize that Blaine has departed, going over "to the dark side."
Tipped off by Jake, Finn takes Ryder to undergo a test that diagnoses him as dyslexic. Ryder feels like he's been concealing a secret identity, afraid of being perceived as stupid and letting his Ph.D. father down. Now set to receive some help, Ryder tells Finn he owes him, but Finn reminds him that he really owes Jake.
Jake notices that Marley's mom has lost some weight, and she in turn encourages him not to give up on Marley and try changing a little - like she has. When Lipoff insults Ms. Rose, Jake stands up to him. A fight is avoided when Ryder and the glee kids rally behind Jake, as Ryder assures Jake he now has his back as well.
In Los Angeles, Puck is working Hollywood Boulevard as a superhero - The Pucker Man - charging for photos with tourists. Jake calls for advice: Can he pursue Marley without screwing over Ryder, who he now sees isn't so bad? Puck says to play it cool and soon Marley will be desperate for him: "Don't be a dick, but don't give up."
Sam tries to convince Blaine to stay, but Blaine confesses his secret: When doubting his future together with Kurt, he hooked up with a Facebook Friend - he realized immediately after how perfect he and Kurt were for each other, but his betrayal ruined everything. Sam urges Blaine to forgive himself, using David Bowie's song "Heroes" to convince Blaine not to exile himself. They're soon on a mission to Dalton, recapturing the Nationals trophy and replacing it with Blaine's Warbler jacket and a note that says "No Thanks."
Ryder postpones his date with Marley to study for an early appointment with a dyslexia specialist the next day. She grows insecure - aided by Kitty's subtle digs about her weight - then confident: Superheroine Marley won't wait around, so she boldly marches up to Jake and asks him out, and he accepts
Blaine returns the trophy and announces that he's staying, and the students present Finn with a gift: a superhero utility belt disguised as a backpack and loaded with goodies, including a treble clef pin to affirm his status as "uniter of glee clubs." As New Directions performs fun.'s "Some Nights," a new unity settles in among the former rivals - except, it seems, for Kitty.