From PEOPLE Magazine Click to enlarge
Finding the perfect dog to play Papi, the tough but tender-hearted hero of the hit movie Beverly Hills Chihuahua, wasn't easy. For weeks trainer Mike Alexander had searched breeders and pet stores before spotting a photo of a big-eared Chihuahua mix named Rusco on a rescue Web site. But the abandoned pup had been at a shelter in Moreno Valley, Calif., for two weeks—and could be put down any day. "The shelter told me to hurry," recalls Alexander, who raced 120 miles to see Rusco.

From the moment he laid eyes on the mutt, Alexander knew he had found a star. "Rusco was sticking his chest out, bouncing around and shredding newspapers," says the trainer, who adopted the dog without hesitation. "He had attitude."

Over the next six months, Rusco learned to jump from a moving van and latch onto a villain's nose. He also settled into his new home, sharing an oversize bed with his Chihuahua costar Angel. "The first time I saw him, I thought, 'This dog is a badass,'" says George Lopez, who voiced Papi's character. "I've got three Chihuahuas at home, and the three combined are not nearly as charming as Rusco." Or as lucky.