Every hero needs iconic enemies who define him as a character. The titular Doctor from Doctor Who is no exception. Since the show first aired in 1963, the Doctor has fought hundreds of enemies. However, the Daleks remain among his most popular villains. They're closely linked to the Doctor and the franchise as a whole, as they first appeared in the Doctor's second adventure.

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These creatures played an important part in the renewed Doctor Who as well, and have served as the catalysts for many events that marked the Doctor's life as well as the lives of many people around them. The Daleks are brilliant, ruthless, dangerous, and have had many great episodes in the show. Some of their stories stand out even among all the competition.

8 Asylum Of The Daleks (New Who, Series 7)

Doctor Who Asylum of the Daleks, eleven carrying amy

While not as great as other episodes, "Asylum of the Daleks" works with an interesting concept: a place full of Daleks who are too unhinged for even the rest of the Daleks to work with and control. And considering the usual Daleks aren't all that stable either, this speaks volumes.

The Eleventh Doctor, Amy, and Rory face the inside of the asylum and encounter many unusual things there, most notably corpses of humans reanimated by a Dalek pathogen. The originality of the idea is enough to make the episode intriguing, even if it lacks the emotional core some other episodes with the Daleks have.

7 The Dalek Invasion Of Earth (Classic Who, Season 2)

Doctor Who The Dalek Invasion of Earth

The Daleks keep coming back, and though the Doctor usually defeats them, it all had to start somewhere. One of the first stories featuring these deathy tin cans happened during the era of the First Doctor, played by William Hartnell. As the title suggests, the Daleks attempted to invade Earth. Their ultimate plan was to turn Earth into a giant spaceship and travel around the galaxy so that they could invade other places.

Luckily, the Doctor managed to stop them during the six-episode arc. This story proves that the Daleks stop at nothing and even though their plans might seem over the top, it still takes a lot of effort to defeat them. For fans who haven't watched any William Hartnell episodes before and they want to give it a try, "The Dalek Invasion of Earth" is a good place to start.

6 Genesis Of The Daleks (Classic Who, Season 12)

Doctor Who Genesis of the Daleks

The episode deals with the question of morality. This time, the Fourth Doctor (played by Tom Baker) has the power to destroy the Daleks before they were created in the first place thanks to his power to travel in time.

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But whether that's the right thing to do, that's a whole other question. If the audience likes to think and learn more about the Daleks' background, this story arc is ideal for them. It allows them to glimpse an interesting side of the Doctor's character as he grapples with this dilemma.

5 Daleks In Manhattan (New Who, Series 3)

Doctor Who Daleks in Manhattan

This story arc has it all: the Daleks, pig hybrids, excellent music, retro atmosphere, and even Dalek-human hybrids. The Tenth Doctor and Martha travel to New York in the 1930s and find out that the Daleks are attempting to create a human-Dalek hybrid.

It's a bold vision that ultimately works, but the Daleks didn't plan that their creation would be much more sympathetic, and, well, human-like. Seeing another form of Dalek added an interesting spin to the species. What's more, the episode also stands out due to its strong supporting cast, which includes Andrew Garfield playing Frank.

4 Dalek (New Who, Series 1)

Doctor Who Dalek

One of the best episodes featuring the Daleks has a simple name and a seemingly straightforward story. The Ninth Doctor and Rose meet a Dalek, whom the Doctor believes to be the last of its species. Rose is sympathetic toward the Dalek, but the Doctor wants to destroy it.

The episode serves to introduce the Daleks to the new audience in the Doctor Who revival, as it's the first time the modern show ever brings them on scene. It also creates a contrast between the somewhat jaded Doctor and optimistic, more innocent Rose. Things get even more intense when the captured Dalek is released and starts killing people. The difference between their two characters emphasizes why the Doctor needs someone like Rose to travel with him.

3 Bad Wolf / The Parting Of The Ways (New Who, Series 1)

Doctor Who The Parting of the Way

The last two episodes of the revival's first season present the type of epic finale any show could wish for. The Daleks attack the heroes in large numbers, and the Doctor proves that even he isn't indestructible, adding a touch of realism to his character. If it wasn't for Rose's heroic actions and the Ninth Doctor's sacrifice, the Daleks would win for sure.

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Despite their defeat, the Daleks still manage to kill a lot of people, including Captain Jack Harkness (who later revives thanks to Rose, but becomes immortal as a result). This two-part story proved once again that the Daleks might look ridiculous to some, but they're deadly and dangerous nonetheless.

2 The Stolen Earth / Journey's End (New Who, Series 4)

Doctor Who Journey's End

Another excellent two-part story, this tale closes the fourth season of the renewed Doctor Who. This time, the Daleks, led by Davros, decide to destroy the entire reality and create the so-called Reality Bomb.

It takes the combined effort of the Doctor and a lot of his friends — Rose, Martha, Jack Harkness, Donna, Sarah Jane, and more — to stop them. Even though they succeed, it's a close call and the Doctor pays the prize for his victory when he ends up alone after everything's said and done. This story also shows the Daleks' frightning ambition, as they're ready to destroy everything.

1 The Daleks (Classic Who, Season 1)

Doctor Who The Daleks

Every story has to start somewhere, and for the Daleks, their story starts here. This episode marks the very first time the First Doctor and his companions, Susan, Barbara, and Ian, meet the Daleks. However, it doesn't yet fully explore the mythology behind this hostile species.

The episode does, however, introduce the Daleks as a genuine threat with no remorse for its enemies. Without this story arc, there would be no future episodes about the Daleks, and they wouldn't be such an iconic and integral part of the show. Even for those who haven't watched classic Doctor Who before should check out this story, because of its significance in the show's history.

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