A prequel to Tenchu: Stealth Assassins, this game shows series heroes Rikimaru and Ayame as teenagers, trained alongside a third young ninja, Tatsumaru, by their aging master Shiunsai. It even reveals how Rikimaru earned the famous scar over his right eye — a detail absent from the cover art.
The Azuma Ninja have served the House of Gohda for generations, and now the three young ninja must defend Lord Gohda Matsunoshin against both an attempted coup and a shadowy ninja organization calling itself the Burning Dawn. The trouble traces back to Lord Gohda's uncle, Motohide, who allied with the warlord Toda Yoshisada to seize the kingdom. Toda's assault on Gohda Castle costs Lady Kei — Gohda's wife — her life and ends with the kidnapping of his daughter, Princess Kiku. Rikimaru stops Motohide from killing Lord Gohda but can't prevent his escape. Motohide is soon betrayed and killed by Toda, who is in turn slain and beheaded by his own chief assassin, Lady Kagami — the founder of the Burning Dawn.
Kagami leads a band of rebel ninja: Suzaku, Genbu, Seiryu, and Byakko, the four Lords of the Burning Dawn. Over time the group turns to kidnapping, theft, forced labor, smuggling, and murder, eventually drawing the attention of Lord Gohda and the Azuma. Worse still, the Azuma's newly named leader, Tatsumaru, has vanished — and is later revealed to have lost his memory and joined the Burning Dawn. With the country at risk of being plunged back into civil war, Rikimaru and Ayame must rescue Lord Gohda and crush the uprising. In the end, the combined might of the two ninja and the naval forces of the Gohda army destroys the Burning Dawn's hierarchy and its flagship, the Fire Demon.