A Zonder motorcycle speeds through a busy freeway, causing property damage and several accidents. At 3G, Leo and Entouji reveal that since the Zonder arrived, a new elemental particle called Z0 which is emitted by their bodies was discovered. They can use these particles to build a sensor that can detect Zonder. Entouji completes the Z Sensor but laments that he could only fit its parts in a backpack. Taiga wonders where Hyuuma is and Swan tells him he’s down at the docks checking for Zonder sightings. Mamoru and his friends witness the chaos on the streets caused by the lack of traffic lights due to the Zonder bike’s nightly rampages. They try to take the viaduct but it too fell victim to the Zonder. Their attention is drawn to someone chewing out a pizza delivery girl for being late while a suspicious motorcycle cop watches them. A news reporter talks about the destruction caused by the Zonder bike just as it speeds by and destroys the camera. The police pursue the bike from both sides but it simply ramps off one of the cars and escapes. Hyuuma suddenly appears on the GunDober and gives chase. The Zonder evades him by driving up the side of the building and Hyuuma is forced to switch to hover mode to avoid crashing. However, he ends up bumping into a billboard and crashing into the water. HyoRyu and EnRyu fish him out and say that they can’t chase after the bike because their bodies are too big. The motorcycle cop watches them from afar. Back in the Big Order Room, Mamoru explains to Guy that it’s possible for someone who was Zonderized to return to their human form to remain hidden. Later, Hyuuma, Kazou and Swan tail a biker who they suspect to be the Zonder. Kazou wonders if it was ok to bring the Z Sensor out for a field test without permission, and Hyuuma says he plans to get paid overtime for testing off-duty. As they’re following the suspect, the Z Sensor picks up the Zonder from a different direction and the bike suddenly appears, smashing the suspect’s bike. It disappears before they could track it and Hyuuma assumes it turned back to human form. Kazou spots a biker gang up ahead and notes that its leader is their second suspect. Hyuuma thinks the Zonder’s reaction disappearing and the gang appearing are not a coincidence. Nearby, Hana and Ayame are camping in line next to the building housing the world bike festival which opens the next day. Hana wonders why they had to come so early when there isn’t a huge crowd and the Zonder bike appears.
The Zonder cuts through the line and knocks over Ayame’s soup pot. Hyuuma and the rest are still tracking the signal, but it disappears just as they find the biker gang wiped out. They pick up the signal again headed their direction fast then disappearing again. The motorcycle cop approaches them, and Hyuuma recognizes him from before. Back at 3G, Taiga discovers Hyuuma’s absence and the missing Z Sensor. The Zonder is traced at the docks and Taiga orders HyoRyu and EnRyu to launch, with Guy and Mamoru riding shotgun. The motorcycle cop questions Hyuuma about the biker gang, and Hyuuma tells him to drop the disguise. The Zonder bike suddenly appears overhead and nearly crushes Hyuuma, but HyoRyu and EnRyu arrive just in time to smash it aside with their cranes. The police officer faints just as the Zonder regenerates and speeds off. Hana begs Ayame to take them home but the latter wants to see what the Zonder bike looks like. The Zonder busts into the bike expo building and assimilates all the bikes inside, turning into a giant robot. Guy jumps in and tells the campers to evacuate. HyoRyu and EnRyu change into robot mode and charge EI-10 with their crane tonfa, but the latter evades and uses its finger tentacles to bind them. Guy summons Galeon and they fuse into GaiGar. Hyuuma and the rest help with the evacuation, and Mamoru notices that Ayame can’t find Hana. Guy uses DrillGao to cut HyoRyu and EnRyu loose then forms GaoGaiGar. EI-10 fires his arm tentacles again but Guy uses Broken Magnum to rip through them and shatter EI-10’s body. The fragments however all reform into smaller Zonder bikes. Guy tries to crush the bikes, but they overwhelm him and restrict his movement with wires. Mamoru finds Hana unconscious in the expo building’s ruins and tries to wake her up. A section of the wall collapses on top of them but a police car suddenly appears and whisks them away. The car tells Mamoru that it will take Hana to a safe place while he goes to help Guy. The bikes drive into every port they can find on GaoGaiGar and detonate while Guy frantically tries to find the original one. Hyuuma tries to use the Z Sensor but it’s useless because the bikes are scattering Z0 particles all over the place. Mamoru flies over to Guy and ignores his warning to stay away because he’s a 3G member as well. Guy snaps his restraints and Mamoru points out one of the prone bikes as the original one trying to play possum. The bike evades Broken Magnum but gets caught by HyoRyu’s Pencil Launcher net while EnRyu destroys the rest of the bikes. Guy uses Hell and Heaven and finally grabs the core. When Mamoru purifies it, the victim turns out to be the pizza delivery girl from earlier. Ayame cries over all the destroyed bikes while the police car drops Hana on a bench behind her. Taiga says that they must study this Zonder more closely. Entouji wonders why it was spreading so much Z0 particles around and Leo remarks that at this rate everyone will be Zonderized.
EI-10 doesn’t top EI-09 on sheer bizarreness value, but nonetheless it’s also unlike any Zonder we’ve seen before. I’m not quite sure why Guy had to use Hell and Heaven on its bike form and still ended up with a large core in his hands. Even stranger is how the delivery girl’s bike was still intact after purification, which has never happened before. On 3G’s side we have several new additions. The Z Sensor was a nice idea but it was made obsolete almost immediately by the Zonder’s new ability to hide its Z0 emission. As for the Pencil Launcher, let’s just say that I’m glad they dropped the stationary motif for new equipment before we started getting things like staple guns and giant duct tape dispensers. The police car was new 3G robot member Volfogg, who’ll get properly introduced in a few episodes. Overall this was a fun episode and it was a nice change of pace to see Hyuuma, Kazou and Swan do most of the legwork out in the field for a change. On a side note, considering Ayame’s track record for visiting locations that are prone to Zonder attacks, Hana might have to reconsider how much she hangs out with her cousin.