Seeing Red is the fifth webisode of season 3.
The webisode starts off in the Super Hero High corridor, with Poison Ivy opening her locker, only to discover one of Harley's pranks popping out, frightening her. Harley begins to laugh as Poison Ivy angrily states her pranks are the worst. Harley then remarks that pranks could only be appreciated by good humor girls. Starfire then flies past them, questioning why they were arguing with each other.
As she further flies past the corridor, Starfire notices further anger spouts, with Hawkgirl angrily throwing The Flash in detention, all the while calling him goody two pants, which beckons The Flash to taunt her further. Starfire then sees Thunder and Lightning arguing over a headband, as well as Vice Principal Grodd smashing up Principle Waller's desk in anger over a vacation, with Principle Waller furiously flipping him against a wall, saying she may of heard him had he been better at pronunciation. In the dormitories, Wonder Woman has Batgirl in her lasso of truth, angrily questioning her on how long she was in the toilet, with Batgirl tossing Wonder Woman a shock-Batarang, zapping her and lunging at her, all the more while calling "Hog-Bathroom Woman".
In Lucius Fox's classroom, Supergirl is trying to laser down Beast Boy, as he lunges and changes into a wolf, trying to bit Supergirl's head. Supergirl, unimpressed, just simply grabbing him and tossing him the air, just as Starfire arrives on the scene. Beast Boy then changes into a tiger, as two begin to clash, However before they can do so, Starfire tries to break up the fight, then seeing the red kryptomite and realizing it as the source of the problems, explaining how it makes humans angry, but aliens like herself, are not affected. Starfire quickly lunges at it, as it begins to run away, lifting up Lucius' box. Starfire then asks Supergirl to help her, with her x-ray vision, but has to convince her, assuring Supergirl, that she'd be sad if Supergirl didn't help, Supergirl then directs her out of the classroom.
In the corridor, Starfire chases after the red kryptomite, however it then uses it's abilities to make Poison Ivy and Harley angry, causing Poison Ivy to pin Starfire to a wall with her giant plants, all the while insulting Starfire's outfit and work effort. In an attempt to stop the kryptomite, Starfire uses Poison Ivy's anger, by insulting her anti-kryptomite formula, which convince Poison Ivy to use it on her, Starfire then breaks free, grabbing the anti-Kryptomite formula from Poison Ivy and spraying the red kryptomite, causing it to shrivel.
Poison Ivy and Harley are then freed from the effects of the kryptomite, with Starfire explaining how the kryptomite made them act that way, Harley then grabs her kryptomite, trying to cover the fact as she does so. Poison Ivy then thanks Starfire for saving them, as Starfire notices she need's a shower, as all the effects of the Kryptomite begin to wear off.