AP casts Blatant Thievery targeting NAP's Mind Control which is enchanting AP's creature. When AP gains control of Mind Control does AP also gain control back of his creature? I'm sure AP does but I just need to check. Thanks in advance.

Yes they do. Since AP now controls Mind Control, they will gain control of the creature. It doesn't matter that NAP owns the Control, since the AP controls the Control now, they'll control the enchanted creature.

Nathan Long
Magic Rules NetRep