He was voiced by the late Rip Taylor.
Mr. Smiley is a pudgy man with brown hair.
He decided to ruin the Otero business by scaring away all their customers by having his girlfriend, Charlene, dressed as El Chupacabra. He already had one of his theme parks in the U.S., but wanted to open up his "Mr. Smiley's Latin Adventure" theme park on the Oteros' property. He even made a fake ghost hologram of the late Señor Otero, lying to the people in the cemetery that were celebrating The Day Of The Dead, that if the Oteros sell their land, the curse of El Chupacabra will go away forever and that Charlene will be returned "unharmed."
Fred took a look at Luis' medallion that Charlene gave him, it was actually a tracking device. There was a red button on the back of the medallion. Fred pushes the button, making Scooby and Chiquita follow the noise made by the tracking device. They stumble upon a nearby tomb, learning that a man in a skeleton costume is controlling the hologram of the late Señor Otero with some video game-like controls. Scooby and Chiquita began barking at the skeleton costumed man to get everyone's attention. The skeleton costumed man tells the two dogs to be quiet, but to no avail, as they continued barking at him. The Skeleton man is unmasked and revealed to be Mr. Smiley. As Charlene is being unmasked by Mystery Inc., she cruelly explains to Luis that she used him for his money, before she and Mr. Smiley begin to express their romantic feelings. Mr. Smiley then explains his plans to Luis and relentlessly teases Alejo about his late father, not before Diego Fuente arrives on the scene, explains to everyone about Mr. Smiley and Charlene's plans and rather than to harm them, he was actually trying to warn them after learning about it and berates them for it.
He and Charlene were then arrested by the Mexican Police and sent to prison for their crimes.
- Even though he and Charlene served as the main antagonists, Mr. Smiley was ultimately the mastermind behind the whole scam.