Dog Whisperer with Cesar Millan

Ashlee Simpson and Pete Wentz hope Cesar can help tame their beloved English bulldog, Hemingway.

A sheepdog-collie mix with severe aggression checks in for a monthlong stay at Cesar's Dog Psychology Center.

A little Lhasa Apso with a huge appetite eats everything she can get her paws on; a 130 pound Great Dane is aggressive around other dogs.

A Chihuahua mix who became aggressive after moving to L.A., a Pomeranian with separation anxiety and an Aussie/shar pei mix with a fear of the sound of coughing.

The host works with three aggressive pups, including two wolf hybrids and a Chihuahua named Nacho.

Erin's basset hound Sadie is afraid of her husband Allen.

Cesar revisits the demonic demeanors of one of Dog Whisperer's most challenging breeds.

Soap opera star Eileen Davidson needs Cesar to help with her roughhousing Wheaten terrier. A Jack Russell terrier has appliance aggression.

At a riding center, the dogs chase after the working horses, and the old mare is frightening the riders.

Old and new cases help show the process for adopting a dog, introducing one into the home.

A pit bull named Britney Dawg knows lots of tricks, but little social etiquette. Also: A dachshund mix exhibits food aggression.

Cesar contends with one of his toughest cases, a red-zone aggressive American bulldog.

A professional dog groomer seeks help handling her toughest clients, including a hyperactive Great Dane.

Cesar Millan goes undercover to investigate conditions at several Los Angles County puppy mills.

When Suzie brought adopted Doberman, Baby Girl home, she wouldn't eat, crawled everywhere.

With two pugnacious pugs and a Chihuahua mix champing at the bit, the Andersons are in desperate need of Cesar’s help.

Roscoe, an Akita, is extremely fearful of the outside. Once a leash is on, Roscoe freezes then pulls back and frantically tries to free himself.

Visiting dog friendly ad agency, Cesar finds three dogs unwilling to play by the rules.

Velvet Revolver drummer Matt Sorum hopes the host can help socialize his French bulldog, Miles.

Sabrina has to ask her Welsh Sealyham terrier, Maxwell, for permission to sit on the couch, and he won't let her sing and dance in their home.

One of John and Maria's two Great Danes, Optimus has bitten John, a neighbor and a family friend. Can Cesar transform Optimus?