Above) Papi, the leading man -- er, dog -- of Beverly Hills Chihuahua (2008), is played by Rusco, and voiced with just the right combination of heroic and comic charm by George Lopez. Papi frankly stole the film, expressive and photogenic and a smart little performer.
Delgado the German shepherd (Andy Garcia) takes over a lot of leading man duties through much of the middle of the film, but never as the romantic lead. It may seem at least partly a mistake to have the romantic lead vanish so long from the tail, but in the original film script, Papi's role was quite small. It was only after Rusco began proving himself a real star in front of the camera that his role was expanded for a more important love-interest.
Below) Montezuma -- "You can call me Monte" -- oozes sexiness as the feral lord of Chihuahua Nation. With his slogan, "We are tiny, but we are mighty," and his revolutionary stand ("No mas!") against humiliating dress-up games imposed on his breed, he would clearly have been the romantic lead if Rusco as Papi hadn't so impressed the filmmakers.
Monte is voiced by opera star Placido Domingo with smouldering authority, entering the tale with something of the same awe-inspiring beauty as we had from Omar Sharif riding in off the desert in Lawrence of Arabia (1962).