Below is a feature breakdown of that episode, along with a few other shows that share the same title (though different season/episode numbers).
In this episode, the resistance continues its struggle against the Espheni invaders with the help of their new alien allies, the Volm. [S3E2] Collateral Damage
Struggles with intense nightmares and a potential mind probe involving his relationship with the alien collaborator Karen. Below is a feature breakdown of that episode,
The plan is nearly derailed by a mole within the resistance who alerts the Espheni. However, Tom uses a decoy team to lure the enemy away while a smaller group successfully infiltrates and destroys the reactor. Character Arcs: The plan is nearly derailed by a mole
While "Collateral Damage" is a common title, these are notable episodes from other major series: "Falling Skies" Collateral Damage (TV Episode 2013) - IMDb