Episode 1 - These Two Are A Best Match
September 3, 2017
• 24 minutes
Unidentified creatures called Smash have appeared at Touto, Sento Kiryu turns into Kamen Rider Build to fight against them. One day, he saves a guy named Ryuga Banjo who escaped from a prison.
Episode 2 - Innocent Runaway
September 10, 2017
• 24 minutes
Because of helping Ryuga, the government chased Build as a wanted criminal. Sento guesses that he can obtain clues to the mysterious organization by finding true culprit who killed Katsuragi.
Episode 3 - Borderline of Justice
September 17, 2017
• 24 minutes
Sento follows the clues regarding Nabeshima, the man responsible for framing Ryuga.
Episode 4 - The Testimony Will Be Zero
September 24, 2017
• 24 minutes
After getting another of his memories back, Sento investigates the connection between Faust's experiments and the Pandora Box; Ryuga tracks down Nabeshima's family and stands up to protect them from the enemy.
Episode 5 - Dangerous Identity
October 1, 2017
• 24 minutes
While confronting Souichi about his connection with Faust, Sento is informed by Sawa about a hint regarding a person who may know his true identity.
Episode 6 - Moonsault of Anger
October 8, 2017
• 24 minutes
Ryuga deceives Sento, and tries to find Faust's hideout by himself.
Episode 7 - The Devil's Scientist
October 15, 2017
• 24 minutes
There is a possibility that true culprit who killed Katsuragi was Sento, but Sento have lost his memory. Ryuga feels a distrust for Sento.
Episode 8 - Memory Starts to Talk
October 22, 2017
• 24 minutes
Sento discovers that Katsuragi was the founder of Faust, and approaches his mother to learn more about Katsuragi's intentions, and obtain more clues regarding his lost memories.
Episode 9 - The Trap of Project Build
October 29, 2017
• 24 minutes
Sento and Ryuga discover that Katsuragi was involved in creating a Build Driver of his own, and his possible involvement with Sento widens the distrust between them.
Episode 10 - Technology of Destruction
November 12, 2017
• 24 minutes
Upon learning of Faust's plan to steal the Pandora Box, Sento and Ryuga set out to Touto Institute of Advanced Matter Physics to protect it.
Episode 11 - Burn, Dragon
November 19, 2017
• 24 minutes
If Blood Stalk's identity is Katsuragi, Ryuga can prove his innocence. But Sento can't control Key-Dragon form's power.
Episode 12 - Conspiracy Theory
November 26, 2017
• 24 minutes
After learning from Sawa about the connection between Faust and Nanba Heavy Industries, Sento and Ryuga confront them to retrieve the Pandora Box and their stolen Full Bottles.
Episode 13 - Who Takes Off the Veil?
December 3, 2017
• 24 minutes
Sento gets a terrible shock, because he learns the identity of the wirepuller from Nabeshima who regained his memory.
Episode 14 - The False Kamen Rider
December 10, 2017
• 24 minutes
An expected person steals Pandora Box, Panels and Bottles from Sento.
Episode 15 - Judge Sento Kiryū!
December 17, 2017
• 24 minutes
Sento and guys were driven into a situation where they had to hide Pandora Box in a old warehouse. They make a decision to uncover a government conspiracy.
Episode 16 - The Weaponry Hero
December 24, 2017
• 24 minutes
It's revealed the real facts of the case that Katsuragi was murdered.
Episode 17 - The Outbreak of the Rider Wars
January 7, 2018
• 24 minutes
As the three countries start a war, both Sento and Ryuga must decide what to do next.
Episode 18 - The Golden Soldier
January 14, 2018
• 24 minutes
Sento confronts Kazumi Sawatari, an assassin from Hokuto, wondering how the enemy got his hands on his latest invention.
Episode 19 - The Forbidden Item
January 21, 2018
• 24 minutes
With he and Ryuga unable to beat Kazumi and his men with their current strength, Sento searches the files left by Takumi to look for an alternative.
Episode 20 - Devil's Trigger
January 28, 2018
• 24 minutes
Soichi approaches Sento and gives him an item that can stop Ryuga's rampage, but using it involves a huge risk.
Episode 21 - The Unstoppable Hazard
February 4, 2018
• 24 minutes
Despite knowing the risks, Sento uses the Hazard Trigger to empower himself against Kazumi's three subordinates. After losing his consciousness and killing one of them, Sento is struck with guilt and refuses to keep fighting, until Soichi gives him an alternative.
Episode 22 - Victory of Tears
February 11, 2018
• 24 minutes
Sento and Kazumi have a duel to settle the war, but when the enemy proves himself too strong for him, Sento has no option but to use the Hazard Trigger again.
Episode 23 - The Phantom of the West
February 18, 2018
• 24 minutes
Taking advantage of the conflict, Seito invades and conquers Hokuto. Now bent on seizing all of Japan, the Seito forces invade Touto, led by the mysterious Kamen Rider Rogue.
Episode 24 - The Man Called Rogue
February 25, 2018
• 24 minutes
Gentoku reappears as Kamen Rider Rogue, determined to get revenge on Touto. To stop him, the other Kamen Riders decide to join forces, when Sento perceives something strange happening with Misora.
Episode 25 - The Idol's Awakening
March 4, 2018
• 24 minutes
Just as Gentoku is about to finish off Sento and the others, Misora appears before them, and the secret behind her mysterious powers is revealed.
Episode 26 - The Treacherous Deathmatch
March 11, 2018
• 24 minutes
Seito challenges Touto for another proxy battle to end the war once and for all. Sento and his friends make preparations to confront Gentoku and his subordinates, unaware that one among them is a traitor.
Episode 27 - The Counterattack Hero
March 18, 2018
• 24 minutes
The proxy battle to end the war is tied with one victory to each side, and for the decisive bout against Gentoku, Sento unleashes a new power.
Episode 28 - The Genius Arrives With a Tank
March 25, 2018
• 24 minutes
Despite using his new powers, Sento is having a hard time against Gentoku, and Sawa reveals to the others the reasons for her betrayal.
Episode 29 - The Opening Bell Rings
April 1, 2018
• 24 minutes
The war between the nations has ended, but Soichi and Namba finally reveal their true intentions as a new conflict begins when they open the Pandora Box.
Episode 30 - The Truth of the Pandora Box
April 8, 2018
• 24 minutes
Vernage, the Queen of Mars possesses the body of Misora to assist the Riders in retrieving the Pandora Box, revealing an important secret about Ryuga in the occasion.
Episode 31 - Surge Out, Magma!
April 15, 2018
• 24 minutes
As the Riders invade the Pandora Tower to retrieve the Pandora Box, a new power bursts from Ryuga, just as questions about his true identity are raised.
Episode 32 - Programmed Tragedy
April 22, 2018
• 24 minutes
Doubtful about his own origins, and eager to know the reason why he was framed in the first place, Ryuga confronts Blood Stalk demanding for answers.
Episode 33 - The Final Weapon: Evol
April 29, 2018
• 24 minutes
Touto's Prime Minister, Taizan Himuro is kidnapped, and Blood Stalk demands Sento to develop a new driver for him in exchange for his life.
Episode 34 - The Best Match is Dissolved
May 6, 2018
• 24 minutes
Having attained the power to transform into Kamen Rider Evol, Evolto infects Sento with a poison, threatening his life should he not relinquish the Fullbottles in his possession.
Episode 35 - Tower of Destruction
May 13, 2018
• 24 minutes
Evolto is close to attain all Fullbottles and the Pandora Box, and with Ryuga under the enemy's control, Sento turns to Gentoku for help.
Episode 36 - Evolto Hunts Planets
May 20, 2018
• 24 minutes
Having finally opened the Pandora Box, Evolto almost destroyed the world, should Vernage had not interfered. However, Sento has run out of options, and decides to risk it all in a move to defeat him.
Episode 37 - The Ultimate Phase
May 27, 2018
• 24 minutes
Evolto avoided his destruction by possessing Sento's body. Now unable to transform, Ryuga looks for a way to save his friend.
Episode 38 - Mad World
June 3, 2018
• 24 minutes
Evolto reaches his full potential and seems unstoppable, while Sento recovers his memories as Katsuragi.
Episode 39 - The Unstoppable Genius
June 10, 2018
• 24 minutes
To face the full power of Evolto and Utsumi, Sento combines the power of all Full Bottles to unleash his most powerful form.
Episode 40 - The Final Revolution
June 17, 2018
• 24 minutes
Surprised with the advent of Build's new form, Evolto decides to begin the last steps of his master plan.
Episode 41 - The Truth of the Best Match
June 24, 2018
• 24 minutes
Sento discover that his father is alive, and by searching the files he got from his mother, he learns why the Rabbit and Tank Full Bottles have a special meaning to him.
Episode 42 - Legacy of Doubt
July 1, 2018
• 24 minutes
With Sento confused with the fact that his father might be in league with Evolto, another person transformed into Kamen Rider Build appears before him.
Episode 43 - Another Build
July 8, 2018
• 24 minutes
As Sento still tries to figure out his father's true motives, Misora is kidnapped by Evolto and transformed into a Smash.
Episode 44 - The End of Evolto
July 15, 2018
• 24 minutes
Kazumi and Gentoku infiltrate Faust's headquarters in Hokuto, but Utsumi appears to face them. Meanwhile, Sento confronts his father, who reveals the true reason why he joined forces with Evolto.
Episode 45 - The Scientist of Hope
July 22, 2018
• 24 minutes
Evolto has been defeated, and Shinobu reveals to the Riders his true objective.
Episode 46 - An Oath to Be the One
July 29, 2018
• 24 minutes
With Evolto one step closer from reaching his objective, Sento and the others prepare themselves for the final battle.
Episode 47 - Zero Degree Flames
August 12, 2018
• 24 minutes
Despite Sento's warnings, Kazumi uses the Blizzard Knuckle to attain a new, powerful form, knowing that he may not survive the transformation.
Episode 48 - To a World of Love & Peace
August 19, 2018
• 24 minutes
With no time to mourn for Kazumi's death, Sento, Ryuga and Gentoku brace themselves for the final battle against a full-powered Evolto.
Episode 49 - The Tomorrow Build Will Create
August 26, 2018
• 24 minutes
After the sacrifice of his companions, it falls to Sento to protect the world by defeating Evolto once and for all.