List of Marvel Cinematic Universe films
Phase One

Film
U.S. release date
Director
Screenwriter(s)
Producer(s)
Iron Man
May 2, 2008
Jon Favreau
Mark Fergus & Hawk Ostby and Art Marcum & Matt Holloway
Avi Arad and Kevin Feige
The Incredible Hulk
June 13, 2008
Louis Leterrier
Zak Penn
Avi Arad, Gale Anne Hurd and Kevin Feige
Iron Man 2
May 7, 2010
Jon Favreau
Justin Theroux
Kevin Feige
Thor
May 6, 2011
Kenneth Branagh
Ashley Edward Miller & Zack Stentz and Don Payne
Kevin Feige
Captain America: The First Avenger
July 22, 2011
Joe Johnston
Christopher Markus & Stephen McFeely
Kevin Feige
Marvel's The Avengers
May 4, 2012
Joss Whedon
Joss Whedon
Kevin Feige

Question: Which is the sequel to the 2008 film Iron Man and which number is it in the Marvel Cinematic Universe list?
Answer: Iron Man 2 is the sequel to 2008's, Iron Man and is the third film in the Marvel Cinematic Universe (MCU).