Entourage is heading for the big screen after a movie adaptation of the show was given the green light this week and with both Mrs Brown’s Boys and Bored To Death also heading off to the world of movies, it got us thinking.

While there have been plenty of films based off of TV, have any kept the same cast of characters and still knocked it out of the park?

If you look at the best films that have come off the back of a TV show, there’s always a big stretch of time between the show and the movie, with a whole group of fresh faces being brought in.

Don’t believe us? Well, look at the evidence. The Fugitive may have been a TV show, but it stopped airing a full 26 years before the film came out. More than enough time for it to have faded into obscurity and audiences simply take the film as its own entity.

Miami Vice and The Addams Family did the same thing. Take a group of characters from an old show and give them a new lick of paint.  Mission Impossible went even further, taking everything but the organisation and concept of spying, throwing it away and starting fresh with a whole new set of characters.

What about cinematic sequels though, as the Entourage movie will surely be? Well, they fair even worse, as while both Sex And The City movies have raked in the cash, they manage to make all the problems about the show even bigger, with the first film basically a massive and terrible episode of the show and the sequel just being offensive, famously making film critic Mark Kermode positively throth at the mouth.

The only time when it’s actually worked was in the case of Serenity. This cinematic sequel to the ill-fated sci-fi show Firefly may have been a financial failure, but was a critical darling and provided the perfect supplement to fans of the show wanting more than the 14 episodes they were given.

The key factor here though is that Firefly set up a universe that could have been explored for years to come and characters whose company you just couldn’t help but want to be in. It also had a trump card in the shape of Joss Whedon. Firefly was his baby, and when it was cruelly taken from him, it was his and the fans continued passion that got a film made. It also doesn’t hurt when you’re one of the best writers in Hollywood when it comes to making a cracking movie.

The Entourage bosses will surely be hoping to mix the commercial and critical success of the two and while we don’t have any more details than a film getting the go-ahead, it might just face a tough battle getting that right.

The trouble with Entourage is that it falls far more in the Sex In The City block than the Firefly block. The show ran for a good few years, clocking up 96 episodes before calling it a day four years ago.

Since then there have been whisperings of a movie, but no massive fan push for it to be brought back to life again. Sure, they'd like to see Jeremy Piven back as Ari Gold, but not to the same levels of devotion other shows have gotten.

Here’s just hoping they know what they’re doing.