"Kamen Rider vs. Hell Ambassador"
Hongo, Takeshi and Taki, Kazuya attempt to infiltrate a Shocker base. After Kamen Ride defeats a revived Kaburong (episodes 65 & 68) the otherwise abandoned base is destroyed by a bomb left behind by Hell Ambassador. In case Kamen Rider and Taki manged to escape Kamikiri-Kid (episode 66), is sent to capture Tachibana, Tobei and the women of his racing club. Shocker puts the women in a jeep like vehicle as a trap for Hongo, Takesh. When he follows, Harinesras (episodes 62, 66) signals his coming. The Shocker soldiers pull over and vanish. When Hongo reaches the women they are attacked from the air by Gokiburi-Ototoko (episode 55), Zemiminga (episode 64) and Kirira (episode 56). When the bombing failes to kill them the three flying insect monsters land to do battle against against Hongo, along with Kamikiri-Kid (who again introduces himself). Hongo of course transforms into Kamen RIder ("Rider Henshin!"). Gokiburi-Ototoko is actually killed (a second time) by Kamikiri-Kid because the cockroach monster told Kamen Rider where to look for new Shocker base. Zemiminga and Kirira simply vanish. As does Kamikiri-Kid.
Kamen Rider on his Cyclone 2 motorcyle attempts to follow three Shocker vehicles to their new base but loses them in a sudden fog (created by Shocker). A motorcycle chase including Jagarman (epsides 53 and 66) and Saiking (episodes 63 and 66) riding motorcycles along with Shocker soldiers insues. Kamen Rider kills the soldiers but the monsters flee. Zemiminga reappears on horse back with more Shocker soldiers also on horseback. Zemiminga reveals Tachibana, Tobe and Yuri tied to crosses (even Shocker isn't brutal enough to nail anyone to a cross). Being a bit too nobel, Kamen Rider doesn't fight back despite his friends yelling at him to let them die and fight back, so he ends up lassoed and dragged behind a horse. (Being merly tied to those crosses with no wounds it would take them days to die of thirst on those crosses but nevermind). Of course Taki, Kazuya arrives in a helicopter (I wonder if Chiba, Jiro could actually fly a helicopter) to rescue Tachibana, Tobei and Yuri so Kamen Rider will fight back. The cowards they are Zemiminga and his soldiers flee as soon as Kamen Rider starts to fight back.
Later, Taki and Hongo arrive at the Mt. Fuji where Shocker has their new base. They have to climb the mountain since Shocker blew up the helicopter. On the mountain they are met by a small army of revived Shocker monsters. Umi Hebi Ototoko (episode 54), Mimizu-Otoko (episode 59), Stingray King (episode 38). Ghoster (episode 41), Pranodon (episode 43), Kinokomorgu (episodes 24 and 25).
Zanjio ("Kamen Rider vs. Shocker", episode 66), Dogumondo (episode 57), Musasabedorl (episode 23), Zanburonzo (episode 29), Frilltokage-Otoko (episodes 58 and 66). Note: most of these are not Hell Ambassador's creations, some of these monsters predate Colonel Zol, some were Colonel Zol's and some Doctor Death's. While Kamen Rider battles the monsters, Taki entes the Shocker base to try to sabotage their new laser weapon. He's caught by Kamikiri-Kid but by then Kamen Rider has entered the base as well. Shocker's base is destroyed by its own laser but Hell Ambassador manages to escape unharmed but . Kamen Rider 1 kills Kamikiri-Kid with "Rider Kick" (but the monster will be reconstructed in episode 66)..
Note: Not all monsters are seen to be killed (again). Those than ran away presusmably surived unless they were in the base when it blew up. Zanjio was last shown taunting Kamen Rider about the laser being aimed at Tokyo, he was gone when Kamen Rider fought Kamikiri-Kid.
This movie features Kamen Rider 1 in his updated form. Kamen Rider 2 is not in it