"Little Toa, you have not yet begun to see even the barest outlines of my plans. I have schemes within schemes that would boggle your feeble mind. You may counter one, but there are a thousand more of which you know nothing. Even my ... setbacks ... are planned for, and so I shall win in the end."
-Teridax to Vakama, Time Trap.
"The Plan" was a term used by members of the Brotherhood of Makuta when referring to Teridax's ultimate goal of overthrowing the Great Spirit. Not all Makuta were enthusiastic about the Plan, or its chances of success, but they went along with it because they knew Teridax would kill them if they didn't. Some, like Krika and Icarax, doubted the Plan would work, while others, such as Gorast, were completely devoted to the Plan, and yet others remained neutral to the Plan's success, like Bitil and Mutran.
Teridax first began to think that it might be possible to overthrow Mata Nui after the League of Six Kingdoms was defeated. Several centuries later, he attacked Mata Nui, making the Great Spirit fall unconscious, and bringing about the Great Cataclysm. Just before the attack, Makuta Teridax placed the Matoran of Metru Nui into spheres that rendered them inert, and caused them to lose their memories. His goal was to later reawaken them and pretend to be their savior, after which they would hail him as their Great Spirit. But his plan was foiled by the Toa Metru, who rescued the Matoran and brought them to the island of Mata Nui.
One year after, Teridax began harassing the islanders by way of Rahi attack, attempting to keep them away from Metru Nui. Eventually the Makuta was defeated by the Toa of Light, and the Matoran returned to their original home. Despite this, Teridax's plan seemed to be intact, and began to enter its final stage.
After being deposited onto Voya Nui in an Antidermis form by the Piraka, Teridax tricked these unknowing Skakdi servants into posing as a Toa team in search of the Mask of Life. After a series of events that brought about the creation of a new, true team of Toa, and the separation of the Ignika from Vezon's skull, the legendary mask flew into the depths of The Pit. Following, Makuta shortly later possessed the mechanical form of a Maxilos Robot, to correct this most recent error.
Keeping his true identity a secret from all but Toa Matoro, Teridax worked to retrieve the Ignika, amid the Barraki and the Toa Mahri. After failing in every attempt, Teridax was eventually frozen by Matoro, only to be freed unintentionally by Jaller's flames. In that moment, he was presented with an opportunity to seize the Mask of Life, but in realizing Matoro's ultimate destiny, he allowed the Toa of Ice to take it. Not long after, Mata Nui perished, bringing the most critical step of Teridax's plan into play. Trusting that the heroism of Matoro would succeed in reviving his "brother", the Makuta returned to Metru Nui, integrating himself into the CPU of the Great Spirit's true body.
After thwarting an attempt to stop his plan by a team of powerful beings, Teridax remained in this location until Mata Nui was revived by the sacrifice of Matoro. Yet, rather than the Great Spirit finally reawakening in command of his fallen body, it was the Makuta who stepped in and took control of the entire Matoran Universe.
In a very short span of time afterwards, almost all of the other Makuta were executed by Teridax as potential threats, and he unleashed hordes of Rahkshi to assault the inhabitants of his new universe. Finally, the Makuta imprisoned Mata Nui's spirit within the Mask of Life, and ejected it into space, rendering The Plan complete.
- Zaktan was the only living being outside of the Brotherhood to be aware of exactly what The Plan involved.