Classic Doctor Who Season 4 Episode 18 The Underwater Menace, Episode 4

The Doctor and his companions arrive in the lost underwater city of Atlantis, where they find a civilization of survivors ruled by a madman named Professor Zaroff. Zaroff is on a mission to raise Atlantis from the depths of the ocean using a device he has created, but his methods are reckless and endangering the lives of everyone in the city.

The Doctor and his companions become embroiled in the political intrigue of the city, helping the rebel leader Thous overthrow Zaroff's tyrannical rule. Meanwhile, they learn that Zaroff's machine is causing catastrophic earthquakes and volcanic eruptions that threaten to destroy the entire planet.

In order to stop the madness and save the world, the Doctor and his companions must navigate treacherous underwater passages, escape from deadly traps, and face off against Zaroff's terrifying sea creatures. Along the way, they meet a group of oppressed workers who have been enslaved by Zaroff, and work with them to take down their oppressor.

With the help of their new allies, the Doctor and his companions successfully infiltrate Zaroff's lair and destroy his machine, saving the city from certain doom and restoring peace to Atlantis. But as they prepare to leave, they discover that one of their own may be in grave danger, setting the stage for a nail-biting cliffhanger ending.

The Underwater Menace is a classic Doctor Who adventure that combines thrilling action, complex political intrigue, and imaginative sci-fi concepts to create a memorable and entertaining episode. Fans of the show will love the dynamic between the Doctor and his companions, as well as the exciting underwater setting and the many dangers they face. With plenty of twists, turns, and surprises along the way, The Underwater Menace is a must-see for any Doctor Who fan.