The Blue Lion plummets toward earth in a tail spin. She is saved, not by any of the VF rushing to aid her in their Lions, but by the tractor beams from a ship piloted by a mysterious stranger - Prince Bokar of Senak.
Lance takes an immediate dislike of the man, In fact, the two have a bit of a rumble right away.
However, since he did save the Princess, he's asked back to the Castle of Lions as a guest. Bokar is the guest of honor at dinner, and Lance couldn't be more annoyed. They put the Prince up for the night and that's when trouble starts. While he sleeps, cobras enter Lance's room through the vents. He awakes and tries to fight them off, the whole while crying out. When the others rush to help, they're also confronted with cobras from the vents. Bokar acts mystified about the whole ordeal.
The next day, the Princess announces that Bokar will be given the key to the Blue Lion. Despite Lance's protests, Bokar is handed the key. It's then that Lance spies something moving underneath the sleeve of Bokar's shirt, so he blasts at it with his pistol. Nanny is outraged Lance fired on their guest, but outrage turns to horror as a cobra falls from Bokar's torn shirt.
Grabbing the Princess, Bokar threatens her with the snake and she faints. With her as a hostage, he takes her to the Blue Lion. It seems Bokar was a minion of Zarkon the whole time. Once in the Blue Lion, he realizes he doesn't know how to operate it. Alfor appears on the Lion's telescreen to prevent the evil man from taking the ship and his daughter. Bokar resorts to forcing Allura to pilot the ship, even making her fire on her friends. Ultimately, he changes into a hideous snake-beast before her eyes. Luckily, the hatch on the Lion opens and he's sucked out of it. Bokar is then turned into a Robeast that the Voltron Force must fight. Of course, he's defeated thanks to the blazing sword.