Basically, the weapon blows up. Archer is seen running away from some explosions in slow motion. Then, Degra's ship returns to the expanse, the bad news about Archer's death is delivered, and the Aquatic ship transports Enterprise back to Earth.
They reach Earth, Tucker and Mayweather take a shuttle pod down to San Fransisco to find out why the hell they can't communicate with Earth, and the shuttle is shot at by some old fashioned WWII planes.
Archer is seen in some kind of Nazi camp and there is a strange blue skin, red eyed alien there. Then, fade to black.
Any theories on what the hell happened?