Graves amenazas acechan a la legendaria ciudad de Metru Nui. Sus habitantes, los Matoran, comienzan a desaparecer sin explicacion aparente y una misteriosa planta ha empezado a destruir la ciudad... Solo los guardianes del bien y la justicia de Metru Nui, los seis guerreros Toa pueden hacer algo antes de que sea demasiado tarde.The city of Metru Nui is divided into six parts. Each part has a guardian - a Toa - who watches over the Matoran who live there. However, somothing strange is happening: Matoran are vanishing and a mysterious plant is destroying the city piece by piece. The Toa have to stop the disappearances and find a way to save their city. Do they have the skills to solve this mystery? Or will they finally meet their match?