After you go west through Route 5 and cross Driftveil Drawbridge, you reach Driftveil City.
Near the entrance of Driftveil, you find a new Team Plasma Grunt talking to an old one. The older one refuses to go steal pokémon with the new guy because he's learned that stealing is wrong. N would be sad if the ex-Plasma guys started stealing again. The new Team Plasma guy says N is a traitor who abandoned them.
Hugh rushes over and knocks the new Team Plasma guy back, then demands more information. The new guy runs away and Hugh runs after him.
The ex-Plasma guy says that Team Plasma split into those loyal to N who want to save pokémon and those loyal to Ghetsis who want to take over the world. The ex-Plasma guy says to visit the ex-Plasma home on the hill.
In the Driftveil Pokémon Center, a girl upstairs gives you some Luxury Balls.
Go north and up the stairs, then east. The ex-Plasma guy notices you and takes you over to Rood. He wants to battle you and will let you into the building if you defeat him. He has a level 27 Herdier and a level 27 Swoobat.
After you win, Hugh shows up and says the Plasma guy got away. Rood lets the two of you into the building. Rood says that the ex-Plasma members have been taking care of the pokémon who had been stolen. Hugh demands to get his sister's Purrloin back, but Rood says that her Purrloin is probably still in Team Plasma's custody.
Rood gives you a Zorua. If you don't have room in your party, go to the Pokémon Center and deposit one of your pokémon into the computer. The Zorua that Rood gives you was originally N's.
In the back, you find Anthea and Concordia. They tell you more about N. He was originally an orphan who lived in the woods with a Darmanitan and Zorua, then Ghetsis took him in and groomed him to become the leader of Team Plasma. Anthea and Concordia were also orphans.
When you are ready, go into the Driftveil Gym.