Original air date: 01/14/2011 Runtime: 22:57 min. A solitary wanderer meets Kai, a young sword-maker, and his sister Nia in their small farming village right before a terrifying skeleton army arrives, ransacking their shop. The army takes a map hidden by their father years ago and Nia! The wanderer turns out to be Sensei Wu, an old friend of their father’s. He promises to help Kai find his sister, but first Kai must become a ninja and master the art of spinjitzu. Kai begins his training and soon meets Sensei Wu’s other ninja’s, who realize they've all been recruited for very specific skill sets.
Original air date: 01/14/2014 Runtime: 22:56 min. Long ago, four weapons of spinjitzu were created by a great warrior. When he passed, his sons were tasked with protecting them. However, the older brother, Lord Garmadon, wanted to use the weapons for his own powerful and evil intents. Sensei Wu was forced to banish his brother to the Underworld and hide the four weapons with dragons as guardians. However, Lord Garmadon has recruited an army of skeletons to find the map that will lead them to the four weapons. Sensei Wu needs Kai, Zane, Cole and Jay to use spinjitzu and the Tornado of Creation to find the weapons first. Only then will the world be safe.
Original air date: 01/11/2012 Runtime: 22:56 min. The four Ninja are snapped out of their post-hero complacency when Lord Garmadon's young son Lloyd shows up and tries to pick up where his father left off. The Ninja dismiss him as a threat, but regret that choice after Lloyd wakes up the evil snake tribe. A prophecy is revealed that states a green ninja will ultimately defeat Lord Garmadon.
Original air date: 01/18/2012 Runtime: 22:56 min. Back in training mode with the looming threat of Lloyd and the Hypnobrai, Zane wanders after a Falcon and lands himself in a heap of trouble. The rest of the Ninja leave the training dojo to help him and return to find that the snakes have burned it to the ground.
Original air date: 01/25/2012 Runtime: 22:56 min. Lloyd, having been kicked out of the Hynobrai snake tribe unlocks a second tribe – The Fangpyres – to help him regain control. The Ninja are busy setting up their new HQ that Zane discovered, but are called to duty when the Fangpyres attack the village where Jay’s family lives.
Original air date: 02/01/2012 Runtime: 22:56 min. After the Fangpyres join forces with the Hypnobrai, Lloyd awakens Pythor – the last remaining snake of the Anacondrai tribe. Pythor lures Lloyd under his spell and steals a map from him that will show him where the remaining two snakes tribes dwell and Uncle Sensei saves Lloyd from doom.
Original air date: 02/08/2012 Runtime: 22:57 min. Lloyd moves in and tries to make nice by helping out with chores, but he just gets in the way. Pythor has awoken the Vipoids and the Constrictaurs and an all out snake war has taken over Ninjago. The Ninja are not faring well, when a mysterious Samurai shows up and saves the day.
Original air date: 02/15/2012 Runtime: 22:57 min. Pythor declares himself to be the destined leader who will reawaken The Great Devourer – an ancient beast who can’t be killed and will consume all of Ninjago. We find out Nya is the Samurai and Lloyd is taken prisoner by the snake tribes.
Original air date: 02/22/2012 Runtime: 22:56 min. When the four ninja follow the mysterious falcon into the woods, they stumble on a hidden work shop where Zane learns the secret about his past and in the process, finally knowing who he is, he is the first ninja to unlock his true potential.
Original air date: 03/21/2012 Runtime: 22:56 min. The ninjas are suspicious when their arch enemy Lord Garmadon moves in to help searching for his missing son Lloyd - but realize they have to work together in their attempt to rescue Lloyd from the snakes inside the unstable Fire Temple that is built on a volcano.
Original air date: 03/28/2012 Runtime: 22:56 min. The ninja and Sensei Wu try to infiltrate the Serpentines’ inner sanctum and walk right into a trap, and when Lloyd’s rescue mission fails, there is only one person who can help them, namely the evil Lord Garmadon – but can they trust him?