Auditions are the norm for newbie performers -- and sometimes even for those with more experience. Some of the tryouts you'll see below led to the gigs that made them famous, while others allowed jumps between TV and film or just the chance to branch out a bit.
Blake Lively'Gossip Girl'
Lively was already part of 'The Sisterhood of the Traveling Pants' when a little show called 'Gossip Girl' came calling, leading her to try out for -- and win -- the role of Serena van der Woodsen.
These days it's hard to imagine anyone but Jackman playing Wolverine, but he wasn't the first choice for the role. When the original actor who was cast had to bow out, 'X-Men' director Bryan Singer remembered Hugh from this audition and brought him in for a screen test.
Rachel McAdams 'The Notebook'
2004 was a breakout year for McAdams -- she proved her comedic mettle as ultimate 'Mean Girl' Regina George and she tugged heartstrings in 'The Notebook.' But first? She had to earn the part.
Melanie Brown, Melanie Chisholm, Emma Bunton, Geri Halliwell & Victoria BeckhamThe Spice Girls
Before they could zig-a-zig-ah, the ladies that would later come to be known as the Spice Girls individually answered an ad and auditioned for the gig first.
In 2003, Carell was beloved by 'Daily Show' fans -- and pretty much an unknown entity everywhere else. But as you'll see in his audition for the movie 'Anchorman,' he was destined for comedy superstardom.
Yes, Fox actually did have to try out for a part in 'Transformers,' and while the film and its sequel made her a star, she was punted from the third installment in the franchise after she compared 'Transformers' director Michael Bay to Hitler -- and ignited the ire of executive producer Steven Spielberg in the process.
Three years into his gig on 'Arrested Development,' Cera auditioned for the movie 'Superbad' -- and won the role thanks to his chemistry with Jonah Hill.
Selena Gomez'Wizards of Waverly Place'
After a regular stint on 'Barney & Friends,' Gomez guested on a couple Disney Channel shows before auditioning for her own series: 'Wizards of Waverly Place.'
Miley Cyrus'Hannah Montana'
She's going out of her way these days to make you forget she was ever Hannah Montana, but back when she was just 11 years old, Cyrus wanted the part enough to audition for it.
Just because she was headlining her own TV show (ABC's 'Alias') didn't mean Garner was above auditioning -- something she had to do to get the role of Elektra in the 2003 movie 'Daredevil.'