On January 8, 2013, it was announced that Reynor was joining Wahlberg in the lead. On March 26, 2013, Nicola Peltz was cast as the female lead. Bay confirmed that the movie was to be in 3D. Bay revealed to Collider that actor Stanley Tucci had joined the cast, and that the film would be the first feature film to be shot using smaller digital IMAX 3D cameras. On May 1, 2013, actor Kelsey Grammer was cast as the lead human villain named "Harold Attinger". On May 6, 2013, actress Sophia Myles was cast in a major supporting role. That same month, Chinese actress Li Bingbing and comedian T. J. Miller joined the cast.
