At a \"magical school for knights in training\" in the kingdom of Astoria, two very different students, Arc and Ciara, form a pact to keep each other's secrets and to follow their dreams of knighthood. Arc and Ciara train with their classmates Prudence and Warwick as well as their rivals Sage and Buttercup so that they would one day be knights and defend Astoria from various threats like its ex-king Ryker and his army.
Knight Squad received a 20-episode order from Nickelodeon in May 2017. Production on the series began in October 2017, and it premiered in February 2018. Tenzing Norgay Trainor has appeared on the series, playing Jimbo in the episode \"The Dork Knight Returns\". On July 27, 2018, the series was renewed for a second season of 10 episodes.
Arc lies his way into knight school in Astoria, by saying he is of knight blood, a requirement to attend; after stealing the Princess' tiara to pay school fees, he joins the school as a member of the Phoenix Squad, led by Ciara. Ciara is the secret identity used by the Princess of Astoria to attend knight school. She uses a magical pixie ring to transform between the Princess and Ciara. After becoming suspicious of each other, Arc and Ciara agree to help keep each other's secret so that they can pursue their shared dreams of becoming knights. Meanwhile, Sage and Buttercup try to sabotage Phoenix Squad's first quest, hoping to get them kicked out of knight school, but they fail.
Arc and Ciara cannot agree on who should compete for the annual Roxbury Cup on behalf of the Phoenix Squad. After Arc finally gets nominated through a coin flip, Ciara nominates herself at the last minute. Arc tries to make Ciara quit by inviting the Princess; however, since quitting the competition would get Ciara kicked out of knight school, Arc and Ciara must figure out how to make it look like the Princess is there while Ciara is competing. When the King demands to speak to the Princess, Ciara must leave mid-competition to save Arc, which means that Sage later manages to win the cup for the Kraken Squad.
It is Armor Day in Astoria and Phoenix Squad is hosting the festivities in knight school. To avoid anyone suspecting that Arc is not from Astoria, Ciara teaches him all the Armor Day traditions; however, when Arc messes up by hiding the symbolic chocolate armor in the wrong place, Ciara and Arc must battle an angry pack rat to get the armor back in time. Meanwhile, Buttercup gives Sage a thoughtful Armor Day gift of a diorama representing how they first met, but Sage gives her nothing. After being tricked by Fizzwick, Sage risks her life to get a unicorn blossom for Buttercup, only to realize that she is allergic.
Sorceress Spitzalot (Mary Passeri) from the sorcery school comes to test any knight school students that may have magical powers so that she can transfer them to her magic school. Warwick tells Arc that he failed the magic spell test on purpose because if anyone found out that he had magical powers, he would be kicked out of school. However, his powers are exposed when he accidentally brings a villain to life from a painting. Prudy, who had been convinced by Sage to quit knight school, returns to help Ciara save the day. The Princess convinces the King to change the rules to let magical students like Warwick remain in knight school.
Jimbo (Tenzing Norgay Trainor), a former member of Phoenix Squad, returns to knight school after being trapped in a cave for months. He takes back his position, forcing Arc out. Later, while Ciara, Prudence, and Warwick are trying to trick Jimbo to quit knight school, Sage recruits Arc to join Kraken Squad. Arc finds out that Jimbo is plotting revenge on Phoenix Squad, and he tries to stop him, but Jimbo renders him unconscious and carries him to the cave. The rest of the Phoenix Squad comes to rescue Arc, but Jimbo traps them there as well. After escaping, they report Jimbo and he is arrested, while Arc rejoins Phoenix Squad.
Tired of Sage pranking them all the time, Phoenix Squad reports her to Sir Gareth, who decides to expel Sage. Sir Gareth calls in Sage's mother Saffron (Maria Canals-Barrera), but Saffron casts an evil love spell on him and makes him favor Sage over the other students. After being reminded that he cannot date students' parents, Sir Gareth decides to make Sage a knight; however, Sage wants to earn knighthood on her own. Before her knighting ceremony, Sage teams up with Phoenix Squad to save Sir Gareth from Saffron's evil spell. Later, Phoenix Squad defends Sage since she did help save Sir Gareth, who decides not to expel her.
Following a magical mishap at the sorcery school, Spitzalot brings her brightest students Team Hex to stay in knight school temporarily, but Team Hex insults Phoenix Squad on arrival. The rivalry escalates when Phoenix Squad is forced to share their squad room with them. When the King orders the two groups to compete for who should remain in the school, Team Hex uses magic to cheat their way to victory; however, they are exposed by Warwick's truth spell. Meanwhile, when Sage makes fun of teaching, Sir Gareth forces her to train a group of little children aspiring to become knights; however, it goes wrong when the children use Sage's lesson against her by pranking her and Buttercup as Sir Gareth gets a good laugh out of it.
Hot shot knight Sir Swayze of Inwood (Jack Griffo) shows up in Astoria and opens up his own academy, which Sir Gareth is against as he had expelled Sir Swayze for his shortcuts and the fact that Inwood will make anyone a knight. Due to Sir Swayze's talents, Arc, Ciara, Sage, and Buttercup want to learn some of his moves, but they cannot let Sir Gareth find out. However, things go wrong when the Phoenix Squad and Sir Swayze reanimate a magical mummy. Sir Gareth shows up and saves them, while at the same time finding out what has been going on.
After Sir Gareth and Hogancross (Fred Grandy) express disappointment in the students being unprepared for a Ryker drill where Sir Gareth posed as Ryker's minion Commander Amballa (Jessie Graff), Ciara tells Arc about how Ryker (Geno Segers) was the king of Astoria until he was overthrown and banished, with Hogancross setting up the dragon crystals which put up a barrier so that Ryker and his forces cannot get in. Arc convinces Ciara to show him the crystals; however, when a crystal goes missing, Arc is suspected of taking it as the barrier starts to weaken, enabling Ryker's forces to invade the knight school. Later, it is discovered that Slobwick, Fizzwick's pet, had snatched the crystal. Arc and Ciara recover the crystal and reactivate the barrier. After the King thanks the students for repelling Ryker's forces, Arc expresses disappointment that his father has not responded to his victory messages; however, Arc's father Zander (Jamie Kaler) shows up and wants to take Arc home.
After making a retreat to Astoria, Ciara doubts that she can help defeat Ryker after seeing Eliza on his side and discards her pixie ring. When Ryker attacks, he takes control of Hogancross, Sir Gareth, and the rest of the knights using the Mark of Ryker spell. The Princess notices the Mark of Ryker on Eliza's hand as the King provides the Princess and Arc with a distraction to get away. Meanwhile, Fizzwick persuades Prudence, Warwick, Sage, and Buttercup to work together to find a spell to defeat the Armor of Astoria. After some persuasion from Arc, the Princess becomes Ciara again and fights Eliza. The rest of the students show up with weapons enchanted by a spell-removal enchantment cast by Warwick as they free Eliza, Hogancross, Sir Gareth, and the other knights from the Mark of Ryker. After Arc knocks Ryker to the ground, the others remove the spell from the Armor of Astoria as Hogancross teleports Ryker away. After the King is freed from the dungeon, Sir Gareth thanks his students and gives them a day off....which isn't really going to give them as there are other threats to Astoria out there. In the final scene, Prudence finds the secret passage to the Princess' bedroom and runs into Ciara there.
When Sir Gareth falls ill, Warwick's father Sir Johnwick becomes the substitute teacher. Wanting to impress his father and make him proud, Warwick decides to use his magic during training; however, much to Warwick's dismay, his father fails him and tells him that knights never use magic and that he is an embarrassment for the family name. Later, Warwick tries to trick his father by using magic on everyone else to mess with their coordination so it looks like he is doing very well in the training without magic. However, his father becomes suspicious and uses a crystal to scan for active magic, revealing that everyone except Warwick has a magical aura, further making him disappointed in him. Warwick decides it is best to get rid of his magic and visits the Witch Doctor. As he is about to lose his magic, Arc, Ciara, and Prudence arrive and attempt to rescue him, but the Witch Doctor uses her magic to place them in chairs they cannot get out of. Sir Johnwick arrives shortly after to rescue Warwick and they both use magic to defeat the Witch Doctor. Sir Johnwick reveals to Warwick that when he was in knight school, there was no magic allowed and he had to keep his powers a secret. Meanwhile, Sage and Buttercup try to nurse Sir Gareth back to full health, but they end up figuring out that he is faking sick in order to get a day off due to fatigue since there is a no days off policy. The King later agrees to give everyone except his guards two days off at the end of each week.
An unexpected attack nearly harms the King and the students' personal weapons have gone missing causing Sir Gareth to do the final exams where Phoenix Squad, Kraken Squad, and Unicorn Squad must find the hidden shields and line them up in order to pass. If anyone gets knocked down, they are eliminated. This competition is fierce until only Ciara and Sage are left wh