Acting on a tip from Daniels, Archer and T'Pol time-travel to the year 2004, where the Xindi are building a secret weapon in an abandoned Detroit factory. They must stop the Xindi from destroying Earth with a biological weapon.

Andorian Imperial Guard Commander Shran arrives in the Delphic Expanse and proposes an alliance with Archer, offering to help steal the Xindi's superweapon. Elsewhere, Lt. Talas, an Andorian officer with her own agenda, helps Lt. Reed repair the Enterprise's damaged weapons systems.