On Quantico Season 3 Episode 12, Alex, Mike, Ryan, and Shelby escort Conor Devlin to Ireland. When the plane gets over Dublin, the cabin pressure drops. Devlin had a man on the inside. He jumps out of the plane, and the rest of our team follows suit.
On the way down, Mike gets separated from the rest of the team, and he lands on the other side of a lake. It doesn't take long before Devlin's guys find him, and he ends up in a prison run by Devlin's people. Devlin even pays him a visit and roughs him up.
Harry, Owen, and Jocelyn rejoin the time (sans Mike) in Ireland. Fiona manages to help the team rescue Mike from police custody. Meanwhile, Owen, Harry, and Jocelyn have been following Devlin's brother, Eamon, and his crew. The find a dead drop, and they coerce the recipient to hand over what he picked up.
It's a tablet that's coded to open to the recipient's fingerprints. On the tablet is a catalog of women for the auction. Maisie is on it.
Fiona is brought in on the recon mission, and she offers up MI5 backup on the raid of the auction, which Mike and Owen approve. Harry and Ryan go undercover as buyers in the auction, where they meet up with Maisie.
While escorting the girls out, Alex and Mike realize that Fiona set them up. Fiona, as it turns out, is intimate with Devlin and owes him her life. Once all the girls, including Maisie, are safe, Alex doubles back to find Fiona. She and Fiona fight, and Fiona ends up dead.
Devlin kills his brother while the team is rescuing the girls, so it looks like he died at the hands of the FBI. Devlin still wants revenge for his son's death; he wants Ryan Booth. Devlin kidnaps Isabella and Andrea to use them for leverage.