A rainy afternoon, all the homework is already done, and there's still a lot of time remaining until dinner. In order to prevent boredom, Sam and Phoebe decide - on a whim - to crack the safe of Sam's dad. For research purposes the Africa expert has brought a creepy ancient African figurine home from his museum, "that surely must be bewitched". Unfortunately, it really is.
"What's the worst that could happen, Phoebe?" are Sam's last words in New York. Then the kids just dissolve into thin air and pop up somewhere in Africa. But why? Did they actually wake up a 500 year old spell? Are they really destined to leave for an adventure that they have not sought but whose heroes they now must become inevitably?
At the Ferdausi lodge in Tanzania Sam and Phoebe get hold of first concrete evidence of the rather nefarious intentions of a certain Max Barran after they have put his hotel room under an unconventional 'inspection'. But that's just the beginning.
Even in the deep rain forests of the Congo Mr. Barran seems to ply his sinister deals -- and after Kohekohe who is of the Mbuti people, is complaining about the relentlessly advancing monster machines in his jungle, Sam and Phoebe again see themsleves forced into another 'inspection'. But this time their findings not only contain top-secret documents and a considerable number of orders of a strange nondescript rock, but they also discover a little bag full of small, heavy stones. Are these stones the key to operations that should remain hidden from the world? And what do Ms. Karimako's monkeys have to do with all this?
After a very small rest in the hyper-modern 'Indigene-Lab' in the Kalahari, our two heroes rescue themselves from great danger only at the last moment somewhere in Cape Town's dark back alleys, only to then find themselves standing eye to eye in front of their powerful enemy. But what was that again, about the little stones from the Congo? Solving this puzzle guarantees Sam and Phoebe a memorable appearance in Mr. Barrans headquarters. Together with their new friends from Cape Town they force the lion temporarily to his knees.
But the story is still far from its end. After meeting with the wise Hekima, whose unwavering belief in a powerful future for Africa also inspires Sam and Phoebe, they rush on to Ghana, spurred by Hekima's great vision. Here, they help the intrepid Ohenewaa and clear up matters in the container port of Tema. But only between the mysterious walls of the medieval library of Timbouctou it seems they might be able to solve the mystery, that could finally bring them back home.
But just now, being so close to their goal, the enemy succeeds with a clever move that they did not foresee. It's now or never. But Sam and Phoebe don't surrender easily. With a caravan they ride north, into the desert ...