While his family is vacationing in Costa Rica at a place called the Divide, the point where water flows to both the Pacific and Atlantic oceans, he passes out and he finds himself in an alternate world, where the Earth's mythical creatures are real and humans are a legend.
Felix and Betony's siblings, Tansy and Ramson, tangle with a cunning japegrin (pixie) named Snakeweed, who markets his company called Global Panaceas, an unscrupulous potions business.
Snakeweed captures Ramson and Felix with the help of his sinistroms (devil-hyenas) Architrex and Vomidor to get information, but unable to extract anything useful, throws them both in jail.
Snakeweed, who also ventured there for publicity, is torn apart by newspapers (introduced into this world by Felix) and Betony's annoying classmate Agrimony (hired as eye candy).
By sheer bad luck, Ironclaw arrives to interrupt Betony and Thornbeak's attempt to neutralize the incendiary spell over the library, accidentally resurrecting a long-dead sinistrom named Harshak.
After a difficult journey across the desert in which the two children are separated from Ironclaw and Thornbeak, they reunite and find Leona at the rock-cut city of Sebeth.
After successfully obtaining the countercharm Felix needs and nearing home, the group are sidetracked yet again by Snakeweed, who attempts to steal Ironclaw's gold.