Season 3 Episode 18: ¥O¬_CØ~1

"While a new infraction brings the team into contact with familiar faces once again, Tom has other concerns. Hellbent on getting his revenge against the woman who destroyed his life, he recruits Sarah to his cause. Meanwhile the QIA, fresh from their victorious return to public favour, sets their sights on their remaining enemies, while Hall must face the consequences of his own actions. However, more twists await as a new attack on the Hubs threatens everything, and the truth about one Agent Carlos Sánchez finally comes to light..."