...And Finally: Black Bolt is the eighth and final episode of the first season of the television series Inhumans.
It's brother versus brother as the final showdown between Black Bolt and Maximus takes an unexpected turn – one with lasting consequences for all of Inhumanity...
Maximus reveals to the rest of the Inhuman Royal Family that he designed a fail-safe to guarantee that his coup would succeed: every hour, he has to connect his palm to the control system of the protecting dome surrounding Attilan. If he does not, the dome will vanish and Attilan will be destroyed. Black Bolt and Triton decide to take Maximus to the control room through the city tunnels while Medusa and Crystal prepare the evacuation of the city. To that end, Medusa uses Lockjaw to teleport to Earth, at Louise Fisher's apartment, and informs Louise that the Inhumans will likely evacuate the Moon. Meanwhile, Karnak is arrested by Maximus' guards and locked in the room where Black Bolt used to confine himself. He is soon joined by Gorgon, who is enraged due to his sudden resurrection and violently murdered Evan Declan.
Black Bolt, Triton, and Maximus make their way through the tunnels. Triton easily dispatches four guards while Black Bolt and his brother keep going. Maximus confronts Black Bolt about the fact that the latter became king although he had previously said that he did not want to. He also reveals that he learnt sign language long ago. While still on their way, the dome weakens further, triggering shaking all over Attilan. Maximus and Black Bolt stumble on several supporters of Maximus, including Loyolis. Black Bolt manages to beat them, but Maximus escapes.
Using his unrelenting force, Gorgon manages to breach through the thick walls of the room, allowing his and Karnak's escape. Karnak and Gorgon later reunite with Triton. Crystal requests Eldrac's help to send all Inhumans to Earth.
Maximus decides to undergo Terrigenesis once again, but discovers that Declan is dead and that the Terrigen Crystals were stolen. Enraged, Maximus summons Bronaja to the throne room and uses his power to have a vision of his future: Bronaja tells Maximus that he saw him as the undisputed ruler of Attilan, without the Royal Family to hinder him. He then heads to the control room with Auran and uses the dome to send a message to the population of Attilan, calling for them to capture the Royal Family. Meanwhile, on Earth, Louise, Crystal, and Medusa ask George Ashland for help in organizing the evacuation. Medusa trusts Louise with the stolen Terrigen Crystals and in return, Louise asks Medusa to take the rocket model of her father to the Moon. Medusa and Crystal then return to the Moon.
Karnak, Gorgon, and Triton discover that Maximus triggered the deactivation of the dome and that only the traitorous Inhuman can stop it. They later reunite with Black Bolt and Medusa. Medusa offers to try one last negotiation with Maximus, ready to exchange peace with a Terrigen Crystal. However, the parley goes wrong and Medusa breaks the crystal before leaving. The Royal Family then addresses the population of Attilan and orders the evacuation. During Medusa's speech, Gorgon leaves and heads back to the palace, with the intent of dying in there. Karnak finds him and apologizes for bringing him back to life, but begs him to come along.
While the population evacuates, all the Royal Family but Maximus meet in the throne room. All of them teleport to Earth, except for Black Bolt, who decides to go after his brother. Black Bolt meets Maximus in the control room, and Maximus reveals that he forged the document advocating a brain surgery on Black Bolt to make him believe that their parents approved it, prompting Black Bolt to confront them on the subject, accidentally killing them with his voice. Maximus tells Black Bolt to kill him, but Black Bolt instead knocks his brother unconscious and locks him in the bunker. Exiting the building, Black Bolt whispers "Goodbye, brother", which collapses and seals the entrance of the bunker, with Maximus inside, left to be the undisputed king of an empty kingdom.
Black Bolt manages to go to Earth thanks to Eldrac. The Royal Family then addresses a message of hope to the relocated population of Attilan.