One of the most successful agents in Hollywood makes 300 calls a day

You would think when you're up in the rarefied air that William Morris agency co-CEO Ari Emanuel inhabits, there's time to sit back and enjoy life.

Turns out it really means you have to work even harder.

In an interview with The Hollywood Reporter, Emanuel - whose client list includes Dwayne "The Rock" Johnson, Charlize Theron, Mark Wahlberg, and Oprah Winfrey (he's also the inspiration behind the loud-talking, aggressive Ari Gold on "Entourage") - reveals that he still hustles for his clients.

The story points out that Emanuel makes up to 300 short calls a day to check in with his massive Rolodex and is often up at 4 a.m.

"When I get in my office at 7:30 in New York, he's the only one I can call - and he's in LA," CBS chairman Leslie Moonves told THR.

"Ari is often calling just to say, 'Can I help? All good? You need anything?'" said HBO CEO Richard Plepler of Emanuel.

In an era when text messaging and email have become the norm for quick catchups, it goes to show that if you want to be that successful, being personable is key.