PORTLAND, Ore. - In what truly epitomized the title of his TV show, "My Cat From Hell," feline behaviorist Jackson Galaxy is calling his attempt to tame the Portland cat notorious for attacking a baby and boxing his panicked owners into a bedroom "the hardest case I have ever worked."

It got more difficult after the happy ending for the cat named Lux soon unraveled.

In the reality show that aired recently, Galaxy persuades another Portland couple to take Lux while the cat is treated with antidepressants and anti-seizure medication. A veterinarian diagnosed Lux with feline hyperesthesia syndrome, which can trigger violent behavior.

But after the episode's taping, Lux attacked his new guardians and they gave him up for their own safety.

"It was the worst letdown," Galaxy told The Associated Press this week. "I don't think I've ever had a bigger shock. This is the hardest case I have ever worked."

But take heart, Lux supporters. The 4-year-old cat has become Galaxy's buddy, and the reality star says he hasn't given up. He's placed Lux in a veterinary clinic where the cat receives medication while undergoing treatment to try to identify what turns this feline Dr. Jekyll into Mr. Hyde.

Lux became one of the most notorious cats in pet history after his owner called 911 on March 9 as the cat terrorized his family. Lee Palmer told dispatchers Lux had scratched his son's head and was out of control. The family barricaded themselves in a bedroom, and Lux could be heard screeching menacingly in the background.

Despite the outbursts, everyone seems to fall for Lux, a long-haired cat with a sweet face. That's the case for Galaxy, who has dealt with thousands of difficult cats.

"I fell in love with him the second I met him," Galaxy said. "He's the sweetest boy in the world."

The reality star has made saving Lux from euthanasia his personal crusade.

The cat is at a clinic where specialists are trying to better understand the complicated feline. Galaxy works with them on treatment, and it's going well so far.

The medication is starting to work. Staff members at the clinic put Lux in different social situations to see how he responds. Galaxy hopes they can modify Lux's behavior so the cat can someday find a home.

"I'm going to keep working with this cat," Galaxy said. "I've got to be sure I give him the best shot."