There were three big developments this week:
- Anne performed surgery on the dead Skitter they had in custody and realized it was once something else. Human, like Ben and Rick, perhaps?
- Pope, via Matt's help, came up with a way to kill Mechs: he used their own metal as a bullet.
- Weaver went with Tom and Hal into town and saw a third kind of alien. It appeared to be in charge of the Skitters and Mechs. After meeting a woman who they later learned was feeding the aliens intel, the trio also saw Karen for the first time: she's totally harnessed and working with the aliens.
We also learned Weaver's backstory: he accidentally killed his own daughter, Sophia, while trying to her her harness off. He almost quit the entire resistance this week, out of guilt and sadness, but then he found his wife's reading glasses in his old apartment and thinks she could still be alive.
We ended the episode just three days away from a planned attack on the aliens' massive structure in town.