Hal Stewart (later known as Titan) is the main antagonist in Megamind.
Hal Stewart was Roxanne Ritchi's cameraman with an obsessive crush on her. Hal appears to live an unhappy life in a small apartment with the mindset of an immature college student. His constant misfortune and inability to earn people's respect and affection cause him to despise life.
After defeating Metro Man, Megamind grows tired of having no heroes to fight and decides to inject someone with Metro Man's DNA. After Hal is accidentally hit by the ray gun with the DNA, Megamind and Minion use their technology to trick Hal into thinking he is an alien and that they are his "space-dad and space-stepmom" respectively. They train Hal into becoming a hero, but Hal's only real reason to become is to impress Roxanne. After the training, Megamind gives Hal a suit and the only name he could trademark, "Titan", which Hal misspells as "Tighten".
Tighten goes to Roxanne and attempts to woo her, but his recklessness and inability to use his power properly causes her to nearly be killed a number of times. After revealing who he is to her, Hal is spurned by Roxanne. Upon later seeing her dating Bernard, who is actually Megamind, Hal gives up on being a hero and decides to use his powers for personal gain. Megamind goes along with his plan to face Tighten but when he never shows up and arrives at his apartment to find him playing videogames, Megamind also sees he has stolen several objects and wishes to become a villain. Disgusted, Megamind reveals to Tighten that he's been tricking him as well as being the man Roxanne dated, causing their battle to go along and Tighten saving the day, as Megamind hoped. However, unlike Metro Man, Tighten has no problem outright trying to kill Megamind, forcing him to flee. Megamind uses a copper sphere, having learned it is Metro Man's weakness on Tighten, but it has no affect, being the first clue Metro Man is alive. Once Megamind flees, the citizens of Metro City congratulate Tighten until he reveals his own evil intentions of domination.
Tighten kidnaps Roxanne, forcing Megamind out of hiding. Disguising himself and Metro Man, Megamind manages to scare Tighten out of the city and reveal himself to the city. However, Tighten finds out he was tricked when "Metro Man" mispronounces the city as "metrocity" something only Megamind does. After finding the device that gave Tighten his powers, Megamind uses it in reverse to take them away.
As Megamind becomes the city's new hero and Roxanne's boyfriend, Hal is thrown into Megamind's former cell.