The Marvel Cinematic Universe's first film was 2008's Iron Man starring Robert Downey Jr.
Iron Man (2008 film) . It is the first film in the Marvel Cinematic Universe . It stars Robert Downey Jr. , Terrence Howard , Jeff Bridges , Shaun Toub and Gwyneth Paltrow . Marvel Cinematic Universe . The first film released in the MCU was Iron Man ( 2008 ) , which began the first phase of films culminating in the crossover film Marvel 's The Avengers ( 2012 ) .