See who Kate Winslet first auditioned with for the role of Rose in Titanic... Because it sure wasn't Leo!

Celebrity Screen Tests

We've been known to spend hours trawling YouTube watching old celebrity audition tapes so we've rounded up a few of our favourites for you to enjoy, below. WARNING: there are tons of them and they're addictive!

TITANIC

It's clear that Kate was pretty much made for the role of Rose DeWitt Bukater but it's just so strange seeing someone be Jack Dawson in DiCaprio's place. Can you have imagined Elton "God, can't you suck?!" from Clueless in place of Leo saving Kate Winslet in Titanic? Well, you no longer need to imagine, check out the below.

THE NOTEBOOK

Much like Kate Winslet for Titanic, it seems that Rachel McAdams was another shoe-in for the role of sassy Ally in The Notebook. Even though he's not in shot, the chemistry with future co-star (and boyfriend) Ryan Gosling is practically electric and if that wasn't enough, McAdams reportedly only got the script the night before this performance. No wonder she got the role.

HARRY POTTER

Now something for the Potterheads - who have no doubt seen these clips a million times - but seeing Daniel Radcliffe, Emma Watson and Rupert Grint all interact with each other on their first ever screen test is just adorable.

THE PARENT TRAP

And speaking of unbelievably adorable pre-fame child actors, enter one Lindsay Lohan whose screen test for her first major movie role in The Parent Trap is so spot on, you might mistake it for the actual scene in the finished movie. Her co-star Dennis Quaid's chat with her at the end is also super, super sweet, as well.

FORGETTING SARAH MARSHALL

The thought of Russell Brand having to have even screen tested for the role of Aldous Snow in Forgetting Sarah Marshall seems kind of odd to us as he made the role utterly his own. Anyhoo, see how Russell made everyone hoot with laughter as he completely improvised this bit in his screen test.

GOSSIP GIRL

And last, but by no means least, enjoy the founding days of Ed "I'm Chuck Baaass" Westwick's audition for the role of, yep, you guessed it, Chuck Bass. Gah! As if anyone else could have been Chuck Bass. Unfathomable.

Although these guys all the bagged roles - save for Elton - some weren't so lucky. Click below for the Hollywood stars who nearly played some of our favourite on-screen characters.