The Seven Crystal Balls begins on a light note, as Captain Haddock tries to adjust to his new life as a gentleman following the events of Red Rackham's Treasure.

He wears a monocle and frequents the music hall, where in a not-unusual coincidence he and Tintin happen to find General Alcazar (The Broken Ear) and the dreaded diva Bianca Castafiore.

However, it's the act of fakir Ragdalam with Madame Yamilah, the amazing clairvoyante, that reveals the central adventure: the scientists excavating the tomb of Racar Capac have incurred the curse of the Inca.

Despite the efforts of bungling detectives Thompson ("With a P, as in Philadelphia") and Thomson ("Without a P, as in Venezuela"), the explorers are stricken, and one of Tintin's closest friends disappears mysteriously, leading to a trip to Peru in the second part, Prisoners of the Sun.