The Omnic Crisis was a global rebellion where automated robotics factories (Omniums) went rogue and began producing armies of hostile robots (Omnics) to attack humanity. The United Nations formed Overwatch, an elite strike team, to combat this threat, eventually ending the crisis and ushering in an era of peace.

After the Omnic Crisis, Overwatch grew into a global peacekeeping force. However, it eventually fell due to internal corruption allegations, the covert illegal activities of its Blackwatch division, and public mistrust. The final blow was the destruction of the Swiss Headquarters, reportedly killing leaders Jack Morrison (Soldier: 76) and Gabriel Reyes (Reaper), leading to the Petras Act which made Overwatch illegal.

Overwatch was the public face of the organization, focusing on peacekeeping, exploration, and scientific discovery. Blackwatch was its covert ops division led by Gabriel Reyes, handling missions that were off the books—assassinations, espionage, and coercion. The exposure of Blackwatch's existence and methods was a major factor in Overwatch's downfall.

Talon is a powerful terrorist organization that operates in the shadows. Their leaders, like Doomfist, believe that conflict and war are necessary to force humanity to evolve and grow stronger. They actively destabilize governments, assassinate leaders (like Mondatta), and incite violence between humans and omnics to plunge the world into chaos.

During a test flight of the Slipstream teleporting fighter, Lena Oxton (Tracer) suffered 'chronal disassociation,' causing her to drift in and out of time. Winston built the Chronal Accelerator to anchor her to the present. It also gives her the ability to control her own time—speeding it up (Blink) or rewinding it (Recall) at will.

Hanzo and Genji are brothers of the Shimada ninja clan. The clan elders forced Hanzo to kill Genji because Genji rejected the clan's criminal empire. Believing he had killed his brother, Hanzo abandoned the clan in grief. However, Genji was saved by Overwatch and rebuilt as a cyborg. They eventually reunited, where Genji forgave Hanzo, urging him to forgive himself.

It appears utopian with clean energy, advanced medicine, and flying cars, but it is a flawed utopia. Anti-omnic prejudice is rampant (e.g., King's Row), corporations like Vishkar exploit populations, and the threat of a second Omnic Crisis looms. It represents a world worth fighting for, rather than a perfect one.

The Iris is a spiritual concept believed in by the Shambali monks (like Zenyatta and Mondatta). It represents a state of transcendence and the belief that humans and omnics possess the same soul or consciousness. It is the metaphysical connection binding all sentient beings together.

The original strike team that founded Overwatch consisted of Jack Morrison (Soldier: 76), Gabriel Reyes (Reaper), Ana Amari, Reinhardt Wilhelm, Torbjörn Lindholm, and Liao (creator of Echo). They were the heroes who ended the Omnic Crisis.

Overwatch 2 picks up years after the organization's fall. Winston issues a recall to former agents (seen in the 'Recall' short). The story focuses on the reformed Overwatch team fighting against Null Sector, an extremist omnic army launching global attacks, while Talon continues its machinations in the background.