They are actually the four horsemen of the apocalypseThis is just from seeing the trailer but... Morgan Freeman is god from the Bruce Almighty movies and feels it's time to unleash some rapture.
"The Eye" is a layberinth sponsored by the Guardians of the VeilThe tarot card symbolism and elaborate, needlessly complex tricks were to help kick start the magician's Awakenings. The Horsemen were chosen because they had skills that the order wanted in agents and the entire plot is to hopefully push them to awaken. Dylan just wanted to get some revenge on the side, but the targets could have been anyone. In addition, the public magic acts help enforce the idea that magic is just an illusion, protecting "true" magic from the masses.
There never was any "true magic"Or "The Eye" for that matter. The ending? Well, five can keep a secret... If four are dead.
The sequel will feature a rogue member of The EyeThe 5 Horsemen will be tasked with tracking them down, using a combination of real magic and their regular skills. The rogue member will be revealed to be the groupie from the beginning of Now You See Me and she will deliver the Wham Line of "I thought you said you'd call me" to Atlas.
Merritt learned how to read people from Psych
True magic isn't real, but the Eye is.