A luckless boy named Ryotaro Nogami comes across a strange train pass and becomes possessed by a powerful demon as he finds himself unexpectedly becoming the hero known as Den-O, fighting strange creatures from another time!

Ryotaro discovers more about his duty to protect the timestream as Den-O as he tries to figure a way to appease Tetsuo before the Bat Imagin can ruin the past.

Momotaros decides to use Ryotaro’s body without his permission, leading to him to become the bodyguard of a minor criminal in need of cash.

Ryotaro, furious that Momotaros had involved him in a robbery, decides to stop asking for the Imagin’s help in battles. Later, the Chameleon Imagin shows up at Yamagoshi’s apartment, leaving the young man large amounts of money and completes the contract with Yamagoshi, allowing him to travel back in time…

Ryotaro soon finds himself involved in a truck accident, losing consciousness, and being possessed by a blue turtle-like Imagin. Momotaros senses this and tried to get the new Imagin out, yet at the same time its personality takes over and becomes the nursing staff’s idol at the hospital, easily wooing any woman that he confronts. As the two Imagin use Ryotaro’s body as a battlefield, another Imagin opens a contract with a young soccer player named Daiki.

Still weary from his battle with the Crust Imagin, Ryotaro has to decide what to do with Urataros, whose lies to allow him to take control of Ryotaro’s weak body and continue his flirtations with the women of Tokyo. The Crust Imagin continues to attack Daiki’s former teammates, until the boy reveals that he was the one initiated the contract. With the contract complete, Ryotaro follows the Imagin and calls on Urataros to unlock a new form for Den-O!

Momotaros tries to prevent Urataros from causing too much chaos with Ryotaro, while Ryotaro sparks the jealousy of the ex-boyfriend of a girl whose home he wakes up in, leading to a drastic confrontation.

Both Ryotaro and his sister Airi work to try and improve relations between the broken couple as Den-O tries to figure out the mystery behind the Imagin’s attacks.

Ryotaro and Hana pursue two Imagin attacking martial artists, one to eliminate rivals while another only seems to try and prove its own strength against other opponents.

Ryotaro tries to discover the truth regarding the karate champion possessed by the Rhino Imagin, while Hana tries to make sense of the Bear Imagin and what he really desires.

Ryotaro becomes the bodyguard of an adoring idol who suddenly finds herself under attack, both in a plot of jealousy and an Imagin, but Kintaros, continually misunderstanding the situation, keeps escalating things and causing more trouble for Ryotaro!

After discovering the Imagin contract holder is Kasumi’s father, Ryotaro tries to discover why as Kintaros keeps trying to resolve the crisis in his own stubborn ways. But when he goes a step too far, his time on the DenLiner looks to come to an end!

Miura believes that Ryotaro is being possessed by evil spirits, and in an attempt to hypnotize him, accidentally awakens an Imagin hidden deep inside Ryotaro. Elsewhere, a man makes a contract with the Owl Imagin in the park in hopes of creating a safe place for animals to live in from the dance group that his young friend is part of…

With the mysterious Imagin, who names himself Ryutaros, now one of the Imagin with connections to Ryotaro, he sets his sights on destroying Ryotaro to become the conductor of the DenLiner while Momotaros, Urataros, and Kintaros put aside their differences try to get rid of him. Meanwhile, Hana tries to find the Owl Imagin and its contract holder, as the Imagin continues to make it so no human may enter the park.

After getting caught up in a robbery, Ryotaro finds himself trapped in a bathhouse by a wannabe criminal with a gun. Just when things couldn’t get worse, an aquatic Imagin begins to run amuck!

As he remains the bathhouse owner’s hostage, Ryotaro tries to figure out the mystery of the man’s relation with his former boss while trying to prevent Ryutaros from dealing with the contract holder his own way.

Ryotaro and Hana decide to clamp down on the Imagin possessing him out of fear for Den-O’s health while Ryotaro encounters a former classmate nostalgic for the past that leads her into a contract with an Imagin.

After his encounter with the shadowy figure that’s been appearing throughout the past, Ryotaro decides to remain in 2004 in hopes of determining if he really is who he appears to be, despite the risk to his life posed by remaining in the past. Meanwhile, the four Taros continue to argue over who will depart in order to ease the burden on Ryotaro.

Yuuto warns Ryotaro about investigating the Yuuto he knew, as the Owner is intrigued by Yuuto’s use of the ZeroLiner, which he believed lost. Deneb attempts a peace offering with the DenLiner crew, while another Imagin rampages, trying to fulfill a contract with a man desperate to find a time capsule he buried a year ago…

After trying to explain to Ryotaro that protecting time and saving people aren’t the same, Ryotaro resolves to prove he can do both, starting with defeating the Jellyfish Imagin. But, as Ryotaro and Momotaros seem outmatched, Yuuto transforms into a Rider!

When Ryutaros grows jealous of Yuuto’s connection to Airi, he possesses Ryutaro, assumes Gun Form, and attacks, forcing Yuuto to use another of his Zeronos Cards. Meanwhile, Deneb tries to help a man who unknowingly enters into a contract with an Imagin while napping…

With Ryotaro putting an end to the fight against Zeronos, Hana asks Yuuto about where the ZeoLiner came from and whether it’s true that it was from her lost time, but he refuses to answer unless she helps Deneb. Meanwhile, the contract holder is laid up in the hospital alongside his boss when he remembers his wish and completes the contract by accident…

A bizarre white Imagin calling himself Sieg has boarded the DenLiner and quickly begins to order the other Imagin around. He explains his strange origins and the connection to the baby he protects, and meanwhile, a man searching for a baby comes in contact with another Imagin…

After Ryotaro is brought in for questioning while trying to return Sieg’s host, Hana tries to teach the troublesome Imagin what it means to be a real, responsible prince. But as he starts to break down, he demonstrates a new power for Den-O…

Ryotaro continues to try and gain the trust of Yuuto, even as he’s being dragged to an important climax! How can he help a young girl and her brother when Deneb and Yuuto keep snatching him away? And why does Yuuto seem to have no idea of what is going on?

Ryotaro continues to attempt to assist the Zeronos in protecting a contract holder from the Spider Imagin even as Yuuto’s future self keeps dragging him to another time! And what is with the mysterious visions of the Imagins that Ryutaro keeps having?

Two Imagin possess a pair of criminals in order to attempt to both attack the present and lure Ryotaro into a trap! Just who is the mysterious man pulling the strings and what is he after?

With Gaoh defeated, a party breaks out aboard the DenLiner, but Ryotaro remembers that the trouble with the jewel thieves hasn’t been resolved! Rushing off to stop the remaining Imagin, he discovers he’s unable to be possessed by anyone but Momotaros as the others begin to vanish, and it’s all thanks to Yuuto’s plan to stop Gaoh…

In order to get better control on using Climax Form, Ryotaro puts the Imagin through a challenge in a haunted house to improve their teamwork, but they find themselves in the center of a murder mystery instead!

Deneb begs Ryotaro to form a contract with him in order to prevent Yuuto from having to use the final Zeronos card as the two find themselves trying to help a man who wants only to reunite with his estranged wife and son and show them his dream…

A former suitor of Airi returns in hopes of winning her heart now that the older Yuuto is gone by offering to help her with a strange debt, while the younger Yuuto is concerned about what the use of the final Zeronos card will mean.

With Ryotaro heavily injured thanks to the Anthopper Imagin, Yuuto and Deneb struggle with using the final card and the permanent damage that will come with it, but when Airi is kidnapped, both Riders jump into action despite the consequences…

As the DenLiner crew discover a strange twisted line in time, Hana suddenly finds herself transformed into a young girl! Could the two be connected? And what’s going on with the piano man wandering about in a trance?

Ryotaro works to discover what the piano man’s true wish could be, which leads him to a comatose piano prodigy, but the Imagin hasn’t stopped trying to fulfill the wish! As the tragic story is revealed, with Yuuto out of action, it’s up to Den-O alone!

Fearing for Yuuto’s ultimate fate due to his knowledge of what happens to those who are forgotten, Ryotaro decides to become strong enough to protect him and time itself. But Yuuto refuses to sit back and watch, as he is offered a new set of Zeronos cards…

With Yuuto resuming use of the cards despite the cost to himself, Ryotaro tries to stop him until Yuuto explains why he does it. But when the two Riders enter battle, Ryotaro discovers that his connection to the Imagin is unstable thanks to the mysterious new line, but the Imagin have prepared for this…

Ryutaros finds himself in conflict when the man behind a mysterious voice that’s been speaking to him arrives and tells him to forget Ryotaro and to target Yuuto instead. Meanwhile, the DenLiner and ZeroLiner arrive at a strange station outside of time…

As the DenLiner and ZeroLiner run out of control through time with Naomi trapped onboard, the crew must figure out how to stop them before they are destroyed while still dealing with Kai and the threat of the Leo Imagin!

While Ryotaro tries to figure out the older Sakurai’s intentions, Kai decides to experiment in eliminating Zeronos in the past, which could have dire consequences for time as Ryutaro knows it!

With the timeline altered due to Yuuto’s erasure, Ryotaro tries to find a way to restore him while also battling against further manipulations by Kai. But when Yuuto reappears, what cost comes along with it?

Shocked by his actions in the timeline without Yuuto, Deneb tries to forge new memories of him,to offset the damage done by the use of the Red Zeronos cards, but even his best intentions may cause even more trouble for Yuuto!

With the discovery that Shouko’s wish is Yuuto himself, Deneb is tasked with taking her on a date to try and draw out the Imagin. Meanwhile, Ryotaro has Owner ask the Station Master about Yuuto’s connection as the key to the junction point…

As Ryotaro comes to realize that defeating Kai would mean the Imagins might vanish, he resolves to prove he can fight on his own without their help…

With Ryotaro continuing to deny the help of the Imagins out of fear of losing them, Momotaros decides to take a stand while the others deal with the stowaway Imagin in the King Terminal.

As Christmas approaches, Ryotaro and Airi receive a strange gift: another watch just like Sakurai’s! Seeking to discover the full truth, Ryotaro tries to find a way to travel back to the day his sister lost her memory to find out what really happened to her and Sakurai…

With the shocking revelation of what really happened the day Sakurai disappeared with Airi’s memory, Ryotaro must piece together how it connects to his own broken memory as the truth regarding the key to the junction point is revealed.

As Kai begins a multi-tier attack to eliminate Airi, Ryotaro and Yuuto desperately try and stop him, but as things look bleak for Ryotaro, Kintaros uses Rayotaro’s New Year’s resolution to complete his contract, taking the Den-O Belt…

Having left Kintaros behind, the DenLiner travels back to stop Kai, but Urataros turns on the others, stranding them a year in the past. It is here that Ryotaro learns the truth of his missing memory and discovers Sakurai’s full plans…

Back in the present, Ryotaro confronts Kai to bring an end to his destruction of time, even if it means eliminating all of the Imagin! The final battle reaches the climax at last!