Shaun and Eds reference to Big Als theory that dogs cant look up came from a scene in Spaced where they were attempting to wrangle a dog into behaving in a certain manner. The scene was explained by Pegg in the outtakes of Paul, a later Pegg and Frost vehicle that didnt feature Wright in the helm. According to Pegg, the inspiration came from a scene where Colin the dog is running away from a block of flats, with the wrangler getting its attention from a ground level despite the on-TV owner being on a high storey in a block of flats. Apparently, they were both worried that the scene wouldnt be realistic enough because the dog wasnt properly looking up, giving rise to the argument. Colin was also supposed to turn up in a cameo in the garden sequences, eating his owner. It had to be shelved because of the British weather.