Tom Cruise tweeted Friday that Mission Impossible 4 is a go, with shooting scheduled to start in Prague this month and in Vancouver in December.

His return to the Mission Impossible franchise seemed almost impossible after a mediocre performance at the box office with Knight and Day alongside Cameron Diaz. Hollywood pundits had been quick to question whether Tom Cruise had lost his star appeal, and ability to bring in large crowds.

Despite the average numbers, Cruise will return as Ethan Hunt in MI4 with director Brad Bird attached to the project. Cruise has been collaborating with J.J Abrams on the script along with writers Josh Applebaum and Andre Nemec. Jeremy Renner (The Hurt Locker) will co-star in MI4. Maggie Q and Jonathan Rhys Meyers have also been cast in the film according to several unconfirmed rumours. The film s leading lady will be played by Paula Patton.

Mission Impossible 4 will likely be the last of the Mission Impossible movies as the franchise has on many levels, almost run out of steam, according to critics, but Paramount aim for an action-reboot with the new outing. A title for the fourth installment has yet to be confirmed, but Aries has been referred to by the production.

Tom Cruise is currently undergoing a fitness regime to look 10 years younger according to Intouch Weekly. The routine will help Cruise prepare for vigorous action scenes and impossible stunts, making them possible for Ethan Hunt in an action packed MI4. Whether the fourth film will be remembered as a classic is another story.

Details of the script have yet to be released, but as shooting starts in the coming weeks through till March 2011, details will begin to emerge. A release for Mission Impossible 4 is tentatively scheduled for the end of 2011