"To love humans, you must know them. You must learn their strengths and weaknesses, beauty and ugliness. Only when you know both sides can you love this planet."
- ―Hideki Go
Deathrem's Plot (デスレムのたくらみ Desuremu no Takurami) is the forty-fifth episode of Ultraman Mebius. It features Mirai Hibino/Ultraman Mebius teaming-up with Ultraman Jack, featuring the return of Jiro Dan as Ultraman Jack's human host, Hideki Go since his recent appearance in Ultraman Mebius & the Ultra Brothers.
Deathrem holds the Phoenix Nest hostage for Mebius' defeat. What can the Ultra do?
The Phoenix Nest is returning from its mission on the moon, but just as it comes into sight, a red light surrounds it and there is an explosion, as the media and public are in an uproar, Hideki Go takes note of the occurrence.
One survivor is confirmed: George Ikaruga. Mirai refuses to believe that the rest of the crew has been killed, and Yuki Misaki tells him she doesn't believe it either. When George awakens, they go to him. George confirms to Mirai that their death is a lie. Mirai is overjoyed, but George remains solemn. He tells them he was sent back to give a message from Alien Deathre: that he will release the rest of GUYS once Mebius is destroyed.
Just then, Deathrem arrives in the city and begins to wreak havoc. Mirai rushes out and transforms to do battle, and the citizens encourage him to avenge GUYS. He is beaten, but during the fight Hideki Go, Ultraman Jack runs up and notices a dimensional warp in which the Phoenix Nest is imprisoned. Deathrem warns them that if they try anything, the humans inside will be killed. He then leaves.
The citizens who were infuriated over the seeming death of GUYS learn that they are being held as hostages, and are infuriated when they find out this is why Mebius did not go all out on Deathrem, because they believe that both Mebius and the remnants of GUYS are prioritizing the safety of their personal friends as opposed to that of the citizens.
This fact strikes Mirai deeply, and he reflects on it. Meanwhile, Captain Sakomizu, trapped in the alternate dimension Phoenix Nest, tells Teppei, George, Konomi, and Marina, that Deathrem is doing this to make a spectacle of Mebius not fighting because of their predicament, severing his relationship with humanity.
Marina tells the others that she was always ready for something like this, and they agree. Teppei decides to send this message out on frequency waves, hoping someone will pick it up and bring the message to GUYS.
Mirai feels depressed, but while he's sitting reflecting, Hideki Go comes up to him, and tells him he's doing fine, and that he must learn of both the good and bad in humanity. He tells him that the Ultras fight for this planet because they believe it's worth fighting for. He tells him that the future of earth is not only in his hands, but also in the hands of the humans.
Deathrem attacks, and Mirai goes to fight him. The humans yell at him for letting hostages sway him, when Deathrem aims bolts at them. Despite their selfishness, Mirai throws himself in the way, blocking the shot.
Then, a civilian picks up the signal the Phoenix Nest was broadcasting on, and sends it to a reporting agency who broadcasts it. "Fight, Mebius. Don't worry about us. Get up. Forget about us," broadcasts through the city.
Mebius attacks Deathrem. Deathrem tries to destroy the ball which holds the Phoenix Nest, but his attack is blocked by Ultraman Jack. Mebius goes Mebius Burning Brave and destroys the alien with the aid of Jack.
Mirai and George are reunited with their teammates, but Alien Groza, the Immortal, is already planning his attack on Earth. End.
- Mirai Hibino (ヒビノ・ミライ Hibino Mirai)/Ultraman Mebius (ウルトラマンメビウス Urutoraman Mebiusu Voice): Shunji Igarashi (五十嵐 隼士 Igarashi Shunji)
- Hideki Go (矢郷 秀樹 Gō Hideki)/Ultraman Jack (ウルトラマンジャック Urutoraman Jakku Voice): Jiro Dan (団 時朗 Dan Jirō)
- Ryu Aihara (アイハラ・リュウ Aihara Ryū): Masaki Nishina (仁科 克基 Nishina Masaki)
- Marina Kazama (カザマ・マリナ Kazama Marina): Ai Saikawa (斉川 あい Saikawa Ai)
- George Ikaruga (イカルガ・ジョージ Ikaruga Jōji): Daisuke Watanabe (渡辺 大輔 Watanabe Daisuke)
- Konomi Amagai (アマガイ・コノミ Amagai Konomi): Misato Hirata (平田 弥里 Hirata Misato)
- Teppei Kuze (クゼ・テッペイ Kuze Teppei): Kenta Uchino (内野 謙太 Uchino Kenta)
- Shingo Sakomizu (サコミズ・シンゴ Sakomizu Shingo): Minoru Tanaka (田中 実 Tanaka Minoru)
- Aide Toriyama (トリヤマ補佐官 Toriyama Hosakan): Kenichi Ishii (石井 愃一 Ishii Kenichi)
- Secretary Aide Maru (マル補佐官秘書 Maru Hosakan Hisho): Yutaka Maido (まいど 豊 Maido Yutaka)
- Yuki Misaki (ミサキ・ユキ Misaki Yuki): Saaya Ishikawa (石川 紗彩 Ishikawa Saaya)
- Kazuya Serizawa (セリザワ・カズヤ Serizawa Kazuya): Shin Ishikawa (石川 真 Ishikawa Shin)
- Ultraman Mebius Volume 12 features episodes 45-47.