Haruka goes Christmas shopping with Kenta and Katori and spots a large reindeer blimp flying overhead. Kenta explains to Katori that Christmas is the day when Santa gives presents to good children and points to a suspicious-looking Santa for reference. Haruka corrects Kenta saying that Christmas is the birthday of Christ who brought love and peace to Earth. As they enter a cake shop, the suspicious Santa turns out to be Satsuda in disguise. Suddenly black snow starts falling. At the Amano Peace labs, everyone is enjoying a Christmas dinner. Hiroshi wishes they had better wine but Haruka reminds him that they can’t afford it because they haven’t settled their year-end finances and taxes. The doorbell rings and it turns out to be Satsuda still dressed as Santa. Satsuda wants to celebrate Christmas with them but the Amano’s are distrustful of his intentions until he wins Hiroshi and Kenta over with wine and gifts. After getting Hiroshi drunk, Satsuda excuses himself to go to the bathroom then starts sneaking around the mansion. He stumbles upon a shaft that leads straight down to the hangar and finds the Fire Jet. When he enters the Baron team hangar, Ace Baron mistakes him for the real Santa Claus. Katori enters the hangar looking for Satsuda but before the latter can hide he succumbs to an unknown illness and collapses. Yoshiko discovers Satsuda’s skin is covered in black spots and has no idea what kind of disease this is. Kenta turns everyone’s attention to a TV news report saying that the mysterious disease is afflicting the city’s population. Just then, Jango hijacks the broadcast and says that if people want the vaccine for the disease they must surrender the planet to him or else the victims will eventually die. Hiroshi orders Kenta to launch with the Space Police and patrol the city for clues. He tells Yoshiko to take the germ sample they extracted to the national hospital for examination. Satsuda suddenly walks into the room and tells them to find a reindeer dropping black snow before collapsing again. Haruka realizes he must be referring to the reindeer blimp and tells Katori to look for it.
On the reindeer blimp, Shura, Zol and Jango spot the Fire Jet heading towards them. The blimp explodes, revealing a giant mechanical reindeer that starts spreading more black snow. Katori sends Kenta to help Yoshiko and combines into Fighbird to face Jango along with Thunder Baron and Super Guardion. Jango reveals the vaccine on the monster’s chest and threatens to destroy it if the Space Police don’t surrender. The civilians plead with the Space Police to give in despite Kenta’s protests. Hiroshi says he has to save Fighbird and starts loading a canister onto the Breaster Jet as a delirious Satsuda watches from afar. The Space Police surrender and Jango fires a paralyzing beam at them. Just as he prepares to cut them up, Hiroshi arrives in the Breaster Jet and fires upon him. He tries to drop a canister of Miracle Coating on the vaccine capsule but realizes that he left the bomb hatch locked. Hiroshi can’t open the hatch with the Breaster Jet on auto-pilot, but Satsuda suddenly reveals himself to have stowed away on the jet and insists that he do it. Satsuda apologizes to Hiroshi for everything he’s done before jumping down onto the canister and pressing the hatch release button. The canister launches with Satsuda still on it, forcing Hiroshi to chase after Satsuda and catch him with a net when he flies off. The canister explodes and covers the monster’s chest with an indestructible coating that prevents Jango from destroying the vaccine capsule. The Space Police quickly break free and destroy the monster’s weapons. Thunder Baron retrieves the vaccine capsule and Fighbird summons the Fire Shuttle and combines into Great Fighbird. Jango fires the monster’s antlers as a last ditch effort but Great Fighbird easily dispatches them before destroying the monster. The next day, everyone recovers from the disease and white snow starts falling. A tax auditor arrives by Satsuda’s request earlier but the latter tells him that the investigation is no longer necessary and dismisses him much to Hiroshi’s shock and relief. Satsuda tells Hiroshi to stop dodging his taxes or he’ll have him arrested. He then tells everyone that they’ll be fighting together from now on. He wonders where the cool guy in the red jacket is, and everyone is aghast that he hasn’t figured out his identity yet.
This is one of the best episodes in a long while. Satsuda finally learns the truth about Hiroshi and the Space Police, ending his long obsession with pinning the money theft on him. He also redeems himself somewhat by releasing the locked bomb hatch and nearly going out in a blaze of glory Segata Sanshiro-style, but luckily Fighbird is not that dark of a show. The rest of the episode goes by fast, but there are still some amusing touches throughout like the Great Brave wine and having a Christmas tree down in the Baron team hangar. Jango’s newest chemical attack is par for the course, but making large quantities of vaccine for it and hanging it out for everyone to see in the middle of a battle was pretty stupid even for him.