Few things immediately identify a television series quite like a great intro.

No opening sequence epitomizes this quite likeLaw & Order(and its many spin-offs).

However, it is truly that DUN DUN that makes theLaw & Orderintro so famous.

Law & Order

Image via NBC

Interestingly, it was in part based on the sample sound of a jail cell door slamming shut.

The intro accentuates these darker, more dramatic beats quite powerfully.

5’Scooby-Doo, Where Are You!'

Law & Order

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The Jeffersons

Image via CBS

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The A-Team

Image via NBC

Helicopter behind the show title from the opening credits of &lsquo;M<em>A</em>S<em>H</em>'

Image via CBS

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Cheers

Image via NBC

Cheers TV Series Poster

The characters run away from something looking scared in the animated series Scooby-Doo, Where Are You!

Image via CBS

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The X-Files

Image via Fox

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The Twilight Zone

Image via CBS

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Friends

Image via NBC

Friends TV Series Poster

The Simpsons

Image via FOX

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Friends

The X-Files