Colonel Porter comes to the 2nd and meets Captain Weaver and Tom to inform that the 7th Mass has been destroyed and he lost contact with the 4th and 5th Mass. He shows a plan to attack the Skitter base structure simultaneously to destroy it. Tom, Hall and Weaver go to find the most vulnerable places to blow up the structure while Pope prepares the explosives. While returning, the see a third species of alien in command of the Skitters. Meanwhile Anne performs an autopsy on the Skitter and finds a harness attached inside.
"What Hides Beneath" is a promising episode of "Falling Skies" with new situations. The discovery of the harness inside the Skitters, indicating that they might be a subdue race. The discovery of a third fish like and tall alien species, probably the leader of the invasion. And the idea of destroying the alien base. My vote is seven.
Title (Brazil): "What Hides Beneath"