Party time in Knighton! The mood is down so the King decides to throw a party. In the meantime Jestro attacks the Fortrex, but he is confronted with the new Nexo Power "The Wedgie of Doom".

Using his Stone to Life magic the Cloud of Monstrox turns Clay into a living, fighting, breathing stone fighting knight. But will Clay use his forces to fight for good or for evil? Does he have a choice?

Clay wakes up in the poor town of Nothing Hill which literally has nothing. Will Clay remember who he is and what he is fighting for? His friends try to help him, but Jorah Tightwad and his Bots get in the way.

The Nexo Knights decide to use Clay to infiltrate the enemy camp but first Clay needs to learn how to be a good spy. Agent Shield, Jack Shield helps them with that.

Jestro and the Cloud of Monstrox builds a new stone army from giant building blocks to crush Knighton. The Nexo Knights try to convince Rockowski, a demolition expert, to help them.

Jorah Tightwad is digging for gold but finds the ancient Lord Krakenskull buried with his army. This stone army is exactly what the Cloud of Monstrox needs.

Clay Moorington the Nexo Knight has had enough of Monstrox, Jestro and their Forbidden Powers and decides to take the fight to them. But the Cloud of Monstrox is getting closer and closer to unleash his master plan.

The giant Stone Colossus is marching on Knighton. Ruina the witch tries to get to Clay, but the other Nexo Knights need him in their final defense of the realm. Which side will he choose? Family or friends?

The Cloud of Monstrox is inside of The Stone Colossus and it now stands in front of Knighton. The students of the Knights Academy are mobilized, the King and Queen are on the defence and the Nexo Knights are ready for the final showdown.