Eleven-year-old Tom Thompson lives with his parents Phil and Patricia and his older sister Lola. The boy is a scaredy-cat and doesn't want to venture into the basement of his home in case something nasty lurks in the darkness. It transpires that a green spectre called Hugo is resident in the basement. Hugo is totally harmless and needs Tom's help to get rid of an Ice Ghost, which chased him out of his old house. If Hugo can't return to his former dwelling, he will vanish forever.