The Night of the Space Spud

There once was a boy who hated potatoes. He hated potatoes so much that one night, in the moonlight, he crept out of bed and into the garden. With the help of his dog, they dug a great big hole and buried all of the potatoes. After they had finished, the boy returned to bed, but all was not as it seemed. The boy was soon woken by a strange noise coming from outside his window. But what was the noise? And what did it want?