Lox, the gate-keeper of the spider kingdom under the hedge in Ben's garden, asks Ben for help again. The Spider Wizard needs three special ingredients before the next full moon to make a magic potion to cure the Spider prince, but can ben find them in time? He meets some unusual creatures on his quest who are not all as scary as they first seem. Ben wants to tell his best friend Jess but she'd rather spend time with the new girl in school, so he asks his gran instead. They look for clues on the computer and in the library, but how much does Gran really know, and will she tell Ben a secret that will keep him safe from Spindra, the evil sister of the Spider Queen?

Ben loves chatting to his wise gran, playing computer games with his best friend Jess, and helping his dad to train his clever dog Scoot. Best of all though, he likes playing ball in the garden with Scoot. Then one hot, summer day Ben meets Lox, the gate-keeper of the spider kingdom under the garden hedge. Lox desperately needs Ben's help before the end of the autumn, but can Ben save the spider kingdom without leaving the garden and going into the deep, dark wood? The leaves are starting to fall, and Ben and Jess must make a brave decision if the spiders are to have a safe winter. Talking to Gran, Ben begins to suspect that she might know more about his quest than she's admitting.

When Ben arrives home from his holidays near the Dark Mountains, he finds out that the lane at the back of his garden is going to be dug up. He's worried because he knows that the spiders who live under the lane will lose their home and could even be hurt. He has to find Lox, the guardian of the Spider Gate to tell him what's going to happen. Ben and his best friend Jess try desperately to think of somewhere that the spiders could live but they only have four weeks before the workmen arrive. Can they find a safe home for the spiders? If they do, how will they move them? Is there anyone who could help? Maybe Gran has some ideas.