"The Fall of Centauri Prime" is an episode from the fifth season of the science fiction television series Babylon 5. This is a key episode in the series, as it marks the final downfall and story completion of Londo Mollari, one of the major characters on the series.

As the episode begins the combined Narn and Drazi fleets are bombarding Centauri Prime from space. In the Royal Palace, Prime Minister Londo manages to get G'Kar out of his prison cell, just before the ceiling collapses.

Londo meets the Regent to try to stop the bombing, but discovers that the latter has been under the secret control of an alien race called the Drakh, so-called "dark servants" of the Shadows, who settled on Centauri Prime after the Shadows' home world of Z'ha'dum was destroyed. They control the Regent's actions via a "keeper," a telepathic creature capable of invisibility, which is attached to him. They threaten to detonate nuclear bombs placed throughout Centauri Prime unless they are allowed to remain there, which Londo has no choice but to allow. The Regent's keeper detaches itself and the Regent dies, and Londo receives a keeper of his own when he is made Emperor.

President Sheridan arrives at Centauri Prime with a small fleet of White Stars and orders a ceasefire. The Narn and Drazi reluctantly agree, but ask Sheridan for aid when the Centauri fleet retaliates. Sheridan refuses, but knows he may eventually have to fight. Meanwhile, Sheridan's wife Delenn and her aide Lennier are trapped in hyperspace after a Centauri attack, their heavily damaged White Star drifting away from the main beacon.

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