What if they were 17 again?

Why should Zac Efron have all the fun? Imagine if Tom Cruise, Johnny Depp and Joaquin Phoenix were 17 again...

The new comedy “17 Again” takes the classic premise of “Big” and spins it in reverse: Matthew Perry plays a middle-aged man frustrated with his life who wakes up one morning to discover that he’s suddenly transformed into a 17-year-old kid played by Zac Efron.

While “17 Again,” opening April 17, offers the vicarious thrill of returning to the care-free days of youth, it also got us thinking: What if some of Hollywood’s biggest stars reverted to their days as teenage newcomers? Would it be cause for concern or celebration? Click on to find out. —S. James Snyder, Special to Metromix