Marvel's Agents of Shield is almost upon us and looks like it will provide a much needed respite from all the heavy drama of series' such as Breaking Bad and Dexter. The series was created by Joss Whedon, the enigmatic writer behind such hits as Buffy the Vampire Slayer and Angel. The series' trailer smacks of action, adventure and the witty dialogue that Whedon is famous for. The mere premise of a team of crack operatives investigating superhero shenanigans in a post-Avengers New York is an intriguing one. People now know about the existence of super-heroes and super-villains, and the threat of those generic fodder aliens coming back is constant and real. All this looks to set up for a series that looks great and can hopefully deliver on the hype. The premise also offers up a chance for a limitless bout of guest appearances from Marvel's extensive catalogue of heroes and villains. Although too many of these cameos would definitely be detrimental to the series, the odd one or two would be fantastic. So that got me to thinking of which 5 Superheroes should pop their heads in and say hi. Let us take a journey into hype, superpowers, and (in some cases) extensive legal ramifications as we look at 'Marvel's Agents of Shield: 5 Superheroes That Need To Make An Appearance'.