Number twenty in the Wallace Boys series. While Zainal was searching the sunken Hana-Maru for treasure, he came across a magnificent kris, the wonderful wavy-bladed knife of the Malays that forms so much of their legends.When the Arabic inscriptions have been deciphered, it leads the boys off in a search of the rain forests of Malaysia for a ruined temple lost deep in the jungles of Taman Negara, the main National Park of Malaysia, encountering much of the wildlife of the Malay Peninsula, tigers, a slow loris, a rather bad-tempered king cobra and the little mouse deer, pelanduk - the animal of so many Malay legends.Their search is complicated by a group of ex-Communists who have returned to the jungle to continue their banditry. From their hide-out, surrounded by lethal booby traps, the outlaws have ambushed the Eastern & Oriental Express Train that plies its luxurious way between Singapore and Bangkok. One of the most elegant of all trains, the Eastern & Oriental is forced to make a detour, and when the raiders board it, they take a hostage in the form of the beautiful Flavia, a rockstar princess.However, an idea taken from Alfred Russel Wallace's book 'The Malay Archipelago', a king cobra, a gecko and a story about a pontianak - a beautiful female ghost - all lead to an extremely satisfactory conclusion.