In the crazy world that is Hollywood, it's important for celebrities to have friends on the inside.
Friends that will understand the pressures of being famous, know how to handle the relentless paparazzi and get to see what you're really like underneath the glitz and glamour of it all.
Watch: Celebs who broke up then worked together. Post continues below.
There are famous friendships like Tina Fey and Amy Poehler that we've known about for years, but there are plenty other unexpected famous friendships that we had no clue existed.
Here are 12 of them.
Katy Perry and Jennifer Aniston
Our first unlikely friendship is Katy Perry and Jennifer Aniston.
The 'Firework' singer and Friends actress have apparently been friends for over a decade and are so close that Perry asked Aniston to be her first child's godmother.