You know, I'm STILL not 100% sure who Lexi is! I also am a bit heavy-hearted over Tom's cliffhanger situation. So much of the fourth season kept the characters apart, it's frustrating to see that they may not begin the fifth season together, either. [though, of course, this show has a history of skipping ahead in time between seasons!] Plus, the potential for Tom's first wife to have become (or have been!) yet another alien creature is too much. I'm sick of the fighting to survive here... why can't we go back to trying to see how a new civilization might prosper?
Falling Skies "Space Oddity" (S04E11): Tom and Anne talk to Lexi, who claims that she wants to fight against the Espheni now, as she can control energy. Tom and Anne both turn her away, but Weaver convinces them to send her on the mission in place of Ben. [whoa.] There's damage to the ship during blastoff, so the ship is losing energy and is very cold, so Lexi has to wrap her and Tom in cocoons. [I'm skeptical...]
Pope shoots at Lexi, but she catches the bullet. In the end, none of it matters. [I hate episodes like this!]
Falling Skies "Shoot the Moon" (S04E12): The bomb has been destroyed because Lexi adjusted power for the sake of the ship. Lexi's "uncle" is there, as is Mira, who prepares to kill Lexi. Lexi claims that she delivered Tom as promised, but when that won't save her, Tom comes to the rescue by stabbing the Espheni. [I was totally ready to kill Lexi for everything she's doing to screw Tom!] Lexi doesn't plan to return home with Tom, but thinks she can remotely pilot the beamer to get him back. [so much more skeptical than before!]
Meanwhile, on Earth, a fog has rolled in that glues people in place. [that just sounds awful!] There are also giant slug-like critters that take over humans. [meh. so many types of danger on this show...] Anne discovers that fire is their Kryptonite, but can't kill them all before she becomes trapped, too, and they're only saved because Cochise's father leads the fight at the moon.
The season ends with Tom in a room with a female critter who seems to resemble his first wife. But, nobody knows he's there, as the beamer went MIA when the power core was destroyed.