20 Amazing Marvel Cinematic Universe Cameos You Never Noticed

4. Shaun Toub (Iron Man 3)

If you don't have a good memory for faces, this is one cameo which would have been very easy to miss. Shaun Toub played a major role in Iron Man as Yinsen, the man who helped inspire Tony Stark to become Iron Man. Five years later, and his return - in a flashback - during the opening few minutes of Iron Man 3 was a very pleasant surprise. The fact that it showed a scene which was referenced way back in that 2008 movie earns it extra props.