Tom Cruise will not be saving the world alone this time around – Paramount Pictures has begun the search for a younger actor to join the aging blockbuster star in his next adventure, Mission: Impossible IV.

This summer’s Tom Cruise action vehicle, Knight and Day, did only moderate business at the box office, which may have contributed to the decision to seek out a costar for Cruise in his fourth outing as agent Ethan Hunt – whether or not that was the plan to begin with is kind of irrelevant at this point.

Mission: Impossible 4 will see Cruise reunited with his franchise costar Ving Rhames, as well as the comic relief in M:I 3, Simon Pegg.  No word yet on whether Michelle Monaghan will reprise her role as Hunt’s wife from the third Mission, though Dragon Tattoo star Noomi Rapace is rumored to be in talks to join the cast.

Deadline is reporting that three actors will test alongside Cruise this week –  Christopher Egan (Resident Evil: Extinction); Anthony Mackie (The Hurt Locker); and Kevin Zegers (Dawn of the Dead).  Readers should expect to hear about numerous other candidates being considered over the next few weeks as well.

Mission: Impossible 3 was the least financially successful entry in the TV show-turned-blockbuster movie series, despite having earned a significantly better critical reception than director John Woo’s second entry.  While audiences may not always agree with critics (and vice versa), it is also possible that Cruise’s appeal as an action star was already fading back in 2007.

Will the addition of a young man just coming into his own as Hollywood leading material ensure that the fourth Mission attracts more moviegoers than its predecessor?  It is difficult to say at this point – especially since the title Mission: Impossible is still synonymous with Tom Cruise for a lot of people.

Mission: Impossible IV is currently scheduled for release in the U.S. on December 16th, 2011.

Source: Deadline