One day, in the city of Night Town, a boy named Hajiki Sanada is assigned to make a special delivery for a very mysterious client. Hajiki accidentally opens the package, only to find a mysterious black cube known as a GAD! The next day he meets a girl named Arashi, and the thieving Jack Gang. The Jack Gang tries to steal the GAD, but when Hajiki bonds with it, the GAD reacts...

After forming a techode from the GAD, Hajiki is confronted by Katana, the pilot of a Heavy Metal named Seven. Hajiki and the Techode manage to drive him and the Jack Gang away. Unfortunately, Katana burns with the desire to destroy them both. Elsewhere, the mysterious client who started this in the first place is revealed; and she wants to claim the Techode as her own... if she can!

Catherine Flaunbert is the new employee at Hachisuka's company and Hajiki isn't too happy about it. Nevertheless, Hajiki follows one of her leads on a GAD to the junkyard. Unfortunately for Hajiki, his hunch was correct, as this just leads him into more trouble, as the Jack Gang and Katana, now sporting their newly formed Techode, Zero, track him down. In the middle of the confusion, Hajiki meets a young girl who owns a Techode of her own...

A GAD is being escorted to the Day Town Museum as a jewel. However, Katana and Wanda soon team up and succeed in stealing the GAD!!

Aiko has an idea that all the Techode owners could be friends. Thus, he confronts Takumi, Hajiki and Katana. Meanwhile, Catherine persuades Hajiki and Lightning to steal a GAD for her that is being smuggled from a museum in Day Town. It turns out the smugglers have hired Katana and Zero as their bodyguards! Aiko and Takumi join in when the GAD bonds with the smuggler and becomes an Atechode. All the Techodes will have to work together to stop it from reeking havoc on the city. But, can this be done...?

Catherine hires Hajiki and Lightning to steal a coffin that a man was supposedly buried in, along with a GAD stone. The police soon catch on, and discover Hajiki. They chase him and accidentally lose the handle of the coffin, which turns out to be the GAD! Meanwhile, Arashi ponders on the idea of having her own Techode. She gets a job in Day Town as a billboard worker. The GAD pieces are loitered all over the town and end up near Arashi. Is it meant for her? Or it something worse?

Two Guardian, or Techode, Hunters have appeared in Night Town to investigate the recent appearances of Techodes all over the city. They soon meet up with Lightning, Thunderbolt, and Messerschmitt, but find it odd that kids are riding them. They are convinced that the teens are being brainwashed by the Techodes and are ready to destroy them. Hajiki tries to convince them that not all Techodes are bad. During the fight between the Guardian hunters and Hajiki, Aiko and Takumi, Catherine and Hachisuka bring Hajiki a very powerful laser to combat the hunters. As Lightning is using it, the laser begins to fuse into Lightning's arm! Hajiki struggles to get through to Lightning, but is this just proof that the Techodes really are as destructive as the two hunters say?

Zero continues to take damage after losing its arm to an Atechode. Thus, Katana sets out in search for repairs. Will she be successful?

Lightning and Lightning are chased through Night Town by Mary and Chris.

Two crime families wage war in Night Town and Hajiki is thrown right in the middle of it!

Hajiki has problems when he keeps getting into trouble for missing his classes. In addition, Hachisuka has assigned him the job of delivering 100 wedding invitations! What a mess!

Hajiki begins to wonder if he’s anything like Katana and what he would be without Lightning. Meanwhile, an assassin named Takanaka targets both Hajiki and Katana. Now, the two have to work together if they hope to survive against this deadly assassin with the ability to gruesomely fuse man with machine!