There are lots of things Algy doesn't like - top of the list is his own name. Algernon is just weird. Pugh sounds a bit like - well, never mind.
Other things on his list include: Girls, the Dark, and Having Adventures. So imagine Algy's surprise when he finds a jungle at the bottom of the garden of his new house! And imagine his irritation when his annoying next door neighbour, Cherry - yes, a GIRL - wants to come and explore it with him. She'll only giggle and whisper if he doesn't go with her. But will they ever make it home again?