A woman and her family pop across the California/Mexico border for a day's shopping and perhaps a little cultural education. While there the kids share their picnic lunch with a stray dog wandering along the edge of a parking lot. The little thing follows them about for most of the day continuing to be fed by the kids and eventually by mom as well. When the time arrives to go back, the kids start the "He's a stray, Mom, can we take him home?" song and dance. Mom, a softy, gives in after deciding they can probably hide the critter in the spare tire well in the trunk just long enough to get over the border. With all their shopping receipts and forms in order, the border guard is satisfied with a cursory check of the trunk and the mother breathing a quick sigh of relief, boogies back into California. The kids play with their new dog all the way home, plying it food until mom, afraid for the upholstery suggests they just let it sleep for a bit.

  Back home, it's accepted by the family's other canine companion, a toy poodle and the last hurdle seems to have crossed. Several days later, however, the family is awakened by bizarre squeals coming from the basement. Telling the children to stay upstairs the mother rushes downstairs. The bloody remains of Fifi the poodle, recognizable by the tufts of white fur left in the trail of gore leading to a new hole in the wall, send the mom back up the stairs in a rush. The father doesn't need to go down before deciding to cal pest control, the exterminator, and local animal control. In the meantime neither mom nor the kids can find the new dog either and they begin to fear the worst.

  Armed with tanks of gas, the long noose on a stick and several nets, the assembled experts head down to the basement. When they emerge an hour later the family is horrified to se their new dog dangling from the end of the pole, clearly quite dead. The animal control officer, confused, dumps the dog in a bag. "Look, I'm sorry about your poodle, but you other dog must be around here somewhere. Probably smart enough to hide and now that we've killed this Mexican sewer rat, it should be safe!