Suzy Johnson is the arch-enemy of Candace Flynn, and a recurring antagonist from the show Phineas and Ferb.
She is voiced by Kari Walghren.
For some reason, she doesn't want any girl other than her to be around Jeremy, her brother. It is unknown why she wants Jeremy to only care for her, despite being already related. Her biggest role in an episode was "Suddenly Suzy". Also in one episode, when Candace finally gets to have a normal day with Jeremy and not spending the entire day trying to tattletale on Phineas and Ferb, Suzy torments her, including putting squirrels in her pants. However, Candace still has a happy day with Jeremy and Suzy couldn't launch her final attack on Candace because cooked steaks have landed on her in a large pile.
In "One Good Scare Ought to Do It!", it has been shown that Suzy also torments the local bully Buford, possibly because he tried bullying her or Jeremy. In turn, Buford is extremely terrified of Suzy, admitting to Phineas that she is so scary that she 'gives him the willies'.
In one episode, Suzy actually sincerely aids Candace, since, as she explained it, Jeremy was not a factor in the situation. However, as soon as he showed up at the end, she again promptly turned on Candace.
- She appears to be the show's most hated character due to her manipulative and psychopathic nature. Not only that, her obsession toward her brother made her some sort of Yandere of the series.
- In a parody of dramatic 'next episode' teasers, the benevolent alien Meap was shown to be having a Matrix/DBZ-like martial arts fight with Suzy. The first sequel episode, 'Meapless In Seattle' originally meant as a joke, was finally made, and featured almost all the scenes the parody teaser showed, albeit placed in awkward ways, also parodying misleading future episode teasers. However, the battle with Suzy never took place, and then was again featured in 'Meapless' next episode teaser ('Meap Me In Saint Louis', which was not made). Heinz Doofenshmirtz, who was breaking the fourth wall, loudly complained that the Suzy/Meap fight had been advertised for that episode, which ended seconds after he said this.
- In the end, Suzy must have been exposed or made peace with Candace, since at least some futures show Candace married to Jeremy.