The Red Skull uses the Doomsday Device on his son Kragov (a.k.a. Reinhold Schmidt) to become the super villain weapon Electro, who can harness energy and bend it to his will. In the comics, Electro was a man named Max Dillon who got electrical powers after working on a telephone pole.
This is the only time Electro appears in this animated series. When the series began, Electro and Sandman were held back from appearing, however, because James Cameron tried for years to write and direct a theatrical "Spider-Man" movie with villains based on Electro and Sandman as the main and secondary villain respectively. The legal rights to the "Spider-Man" movie went into limbo for over a decade, with Electro and Sandman based characters still intended to be the villains. However, when it became clear Cameron was not going to make a Spider-Man film, writer John Semper was able to include Electro into the series, but not as Max Dillon and he was not an American. Instead, a new character with a new back story was created for the show since the creative team were already developing The Six Forgotten Warriors arch.
This version of Electro is much more powerful than any previous version. He shuts down all of New York City saying that is a small sample of what he can do and he not only controls power, he is power. He is even able to take down the whole S.H.I.E.L.D. Helicarrier.
This episode is loosely inspired by "The Amazing Spider-Man" (Vol. 1) #9, the first appearance of Electro and his first battle with Spider-Man.
Captain America was fascinated by Whizzer's portable television calling it "a miniature portable imaging device". This is because Captain America was hidden away for over 50 years.