Favreau and Paltrow returned in the sequel Iron Man 2 , released on May 7, 2010. Downey also made a cameo appearance as Stark in The Incredible Hulk . Contents 1 Plot 2 Cast 3 Production 3.1 Development 3.2 Filming 3.3 Effects 3.4 Music 4 Release 4.1 Marketing 4.2 Reception 4.3 Box office