Five years ago a mysterious world-changing event revealed the existence of super-powered humans to the world. As the world struggles to acclimate to the new reality, more and more super-powered people come out of the woodwork as heroes and villains, including Toronto's semi-famous hero Thunderbird. Sara Strong has known about her powers her whole life and is ready to join the fight, even if it's against her parent's wishes. Meanwhile, two scientists discover something sinister going on at the world's premier institute for super-powered beings. And a mysterious woman returns to the city for some unfinished business.