In less than 72 hours, this very red carpet where I'm standing is going to be choke a block full of the most famous stars in the world. While inside it may be all about the movies, outside it's all... See More
In less than 72 hours, this very red carpet where I'm standing is going to be choke a block full of the most famous stars in the world. While inside it may be all about the movies, outside it's all about the dresses. The style wars out here may be just as important as the battles inside in two of the most powerful stylists to the stars are taking us behind the scenes to see what it taeks to get red carpet ready. The awards may be presented inside, but these days, outside on the red carpet winners and losers are also crowned. And out here, the stakes are make or break high. A whole lot of casting directors are watching. I long with $40 million other people. A dress can change things for girls. Do you believe that? Absolutely. A fashion fail can hurt more than feelings. It can harm your career. Who could forget Cher's mohawk or York's swan dress. But that was before the rise of the celebrity stylist who become stars themselves. Written about in this month's "Vanity fair." Ten years ago, people who were celebrities used to go to parties with perhaps a publicist. Now the plus one is the stylist. The stylist is really the most important person in the entourage. Image is power in Hollywood. And two of the biggest celebrity stylists pull back the curtain of that secret world for us. Okay, come on. Are these the Oscar dresses? These are the Oscar dress. This thing must weigh ten pounds. Do you think we'll see this on the red carpet? You might. Nobody can just buy one of these dresses. They are one of a kind. I guess you would say good luck if you think it's easy to get the dress. Good luck, exactly. Spend an hour with me. And wildly expensexpensive. They go up to $100,000. This could be a winner's dress for sure. Absolutely. Reporter: To snag one requires months of negotiations, strategizing and sometimes even sharp elbows. It certainly requires hitting the pavement. And lots and lots of fashion shows. And that's where the stylist comes in. The person in charge of making sure the star is runway ready from head to toe. Isn't that incredible? Anyone can call themselves a stylist at the tippy top, there are only about 20 who matter. Leslie freemar is all in the front row. Everybody doesn't get every dress, right? Oh, only one person gets the dress. Over here, please, please. It helps when you have clients like she does, women known for their style. Jennifer Conley and scarlet johanss Johansson. So it's both the clout and the clout of your client pop even event and how much exposure it will get. Her fashion bonifieds run deep. She got her start as an assistant memorialized in "The devil wears Prada." Your incompetences doesn't interest me. Rsvp yes. Drop me off the 9:30 and pick me up at 9:45 sharp. When Leslie hook me to the Michael cors boss, her old boss was a few feet away. She's just very professional and gets it done. Reporter: Freemar shows us some of the designs her clients have worn. This is actually a dress that Christian dior made for Charlize for the golden globes. This is an old dress when Johnny Diano was at dior. It got mixed review, but I really loved it. In fact, this dress was largely panned. Ci in nnnabon. What is she doing? That's not very nice to hear, but Joan rivers is a comedian. She's not a fashion critic. So you have to take those things with a grain of salt. Reporter: So when you hear it's been less than 100% successful, what do you do? Do you call her? Yeah, you call her and you see are you okay? And she'll be like I'm fine. Okay, let's time it will be a home run. Leslie is again styling Charlize for the oscars. It's only a few days away. I assume the dress is made at this point. I wouldn't B assume that. It's being made probably as we speak. Someone is sewing somewhere. A lot of people are sewing. Meanwhile, out in Los Angeles, Carla Welch is getting two stars ready for the big night on Sunday. She's known for putting Justin Bieber in the drop cross pants. Can you tell me who you're dressing for the oscars? No. One of them is very top secret. Top secret? I fought for this dress. People wanted this des. And it's nerve wracking because award season is, like, the flu. It goes on and on and on and on. . Reporter: Awards season is like the flu? It goes on forever. Of course, it's not just Oscar season. Stylists are busy year round. Whenever a major star goes on the road to promote a movie, it means she'll need dozens and dozens of outfits. If you put a star in a dress that someone had once worn? This is the death of a stylist. Reporter: The death of a stylist. I was being dramatic. If you're wondering if what an actress years makes a difference, consider lupit Lupita nyongo. Nominated as best supporting actress for "12 years a slave." Somebody like Lupita nyongo is incredibly beautiful, incredibly hot actress nobody has really known her before. Her talent got her nominated but her style has launched her into a whole new level of fame. You might get a role because someone saw you in that red dress or green one. O. Absolutely. 100%. Reporter: That's a lot of pressure. Yeah, sure. But it still has to be fun. Everyone is screaming your name. I love you, Meryl!
This transcript has been automatically generated and may not be 100% accurate.