Maxwell Dillon has been one of Spider-Man's most frequent and enduring adversaries, often fighting alongside some of the more powerful masterminds in the web-head's rogues gallery, rather than creating intricate plots of his own. Raised by his overprotective mother, after his father abandoned them, Max had ambitions of being an electrical engineer. However, after being convinced by his mother that he was not smart enough to pursue such a career, Max instead reluctantly took a job as a lineman for an electric company. While repairing a power line still connected to its spool, Max was struck by lightning. Instead of being killed, the freak accident caused a mutagenic change in his nervous system, allowing him to generate and control vast amounts of electricity. After creating a colorful costume, Max turned to a life of crime as Electro.
At the beginning of Electro's criminal career, J.Jonah Jameson began a smear campaign in the Daily Bugle proclaiming Electro to actually be an alter-ego for Spider-man. Intent on proving the publisher wrong, Spider-man faced Electro and was nearly killed by merely touching him. Using a fire hose, however, the web-slinger was able to defeat Electro. Sometime later in another attempt to deface Spider-man's reputation, Jameson secured Electro's supercharged services to battle the web-slinger on national television. Before an audience of millions, Spider-Man stood triumphant once more. Dillon was humiliated.
After a string of embarrassing defeats, decided to test his strength in numbers as a member of the Sinister Six, alongside Doctor Octopus, Kraven the Hunter, Sandman, Mysterio and the Vulture. Drawing numbers, the plan was for each villain to face Spider-man in a different location that drew upon their respective talents one by one until one of them was victorious. However, they were eventually defeated and imprisoned.
In an attempt to win himself the glory and respect that had alluded him so frequently, Dillon tried to devise a master plan to control New York City's power supply. However, he was once again defeated by Spider-man and convinced to quit his criminal career...if only temporarily. He resurfaced as a member of the next incarnation of the Sinister Six, with Hobgoblin replacing the deceased Kraven the Hunter. Doctor Octopus betrayed the group and they were subsequently disbanded.
Electro was also a member of Mysterio's Sinister Seven, created to combat Spider-Man's insane, homicidal clone, Kaine. However, Kaine disappeared and with no further need to keep the group together, it was disbanded and Dillon returned to his self imposed exile
He was once again brought out of retirement by the Rose, who offered Dillon the chance at an experimental procedure to greatly enhance his abilities in exchange for his services as an underworld enforcer. Dillon and agreed, sensing the opportunity to rise above his past failures. After undergoing the procedure and dispatching several members of the True Believers, an offshoot of the Hand at the request of the Rose, Dillon returned to his original plan of taking over the New York City power supply. Once again defeated by Spider-Man, who had donned an insulated suit, a frustrated Dillon threw himself into the Hudson River, apparently killing himself.
However, Dillon survived as he reappeared as part of the next series of subsequent incarnations of the Sinister Six, each of which were either defeated or disbanded due to internal conflicts. The most recent incarnation, the Sinister Twelve, gathered by the Green Goblin as part of a larger plan to enable his escape from prison and destroy Spider-Man. They were defeated with the help of the combined efforts of Captain America, Iron Man, Daredevil, Yellowjacket and the Fantastic Four.
Electro was hired by Brainchild to free Karl Lykos from the Raft, a maximum-security prison designed to hold supervillians. Electro initiated a prison break the likes of which had never been seen, releasing scores of criminals. However, his actions also brought together a number of the world's most powerful heroes to contain the disaster including: Captain America, Iron Man, Luke Cage, Spider-Woman, Matt Murdock, Sentry and Spider-Man, many of whom were trapped in the Raft when the power was shut off. With the exception of Daredevil (and Sentry at first), this impromptu gathering of heroes reunited shortly after the prison break to form a new Avengers team. Dillon tried to escape with his girlfriend, a waitress in Boston, but was captured by the new Avengers, the very team he inadvertently helped create.