From TNT:

On the heels of Tom and Lexi's successful albeit tragic mission to destroy the Espheni power core on the moon, we pick-up with Tom's life hanging in the balance as his Beamer drifts into space. While onboard the beamer, Tom encounters a surprising guest who urges him to find his inner warrior. Meanwhile, back on earth Anne reluctantly steps into Tom's shoes to help lead the 2nd Mass in his absence. Against all odds, Tom makes a miraculous, yet mysterious return to earth. Once reunited with the 2nd Mass, Tom shares a new plan for winning the war. The Espheni, for the first time, are on their heels and the 2nd Mass will not rest until they are gone from this planet for good.