Skynet has been restored by the machines ever since Legion was destroyed. Now that the opposition is aware of their plans, they need to figure out how to stop them.
Storyline
The Machines have been working in a way to restore Skynet back on, since Legion was destroyed, now the resistance discovered their plans and must find a way to prevent that from happening, and for that they must go underground to Gideon the new home-base of the machines