Gregory Gideon was one of the wealthiest, most influential men on the planet. He valued money over everything, even ignoring his own wife and son.
When he attempted to buy out the three remaining financial companies he didn't own, they set him a challenge they believed impossible: destroy the Fantastic Four. Gideon accepted the challenge, using his employees and connections to trick The Thing into thinking Reed Richards was a Skrull and make Johnny Storm think his sister Sue was under the Puppet Master's control.
While the Four fought amongst themselves, Gideon set in motion the final phase of his plan: to boobytrap the FF's Time Platform into sending them into the past. Gideon's son Thomas overheard his father's plan, and raced to warn the heroes, inadvertantly falling into the trap himself. Fortunately, Thomas was brought back by an automatic failsafe after Reed shut off his lab's power. Realising that he had almost lost his son, Gideon gave himself up to the police, vowing never to put money over his family ever again.
Some time later, Gideon discovered he was dying. Donning a powered suit, he had Dragon Man capture Sue Storm, in a bid to force Reed Richards to cure him. It was Thomas once again who convinced his father to stop, and Gideon decided to spend what time he had left with his family.
While flying in a private jet, Gideon and his wife were killed when their jet was caught between Russian nuclear tests. Thomas survived, becoming Glorian soon after.