Some shows feel eternal. Mostly because they've been on the air for so long, we can hardly remember a time when they didn't exist. Such is the case of Law & Order: Special Victims Unit, the most famous spin-off of the equally long-running show Law & Order. First premiering in 1999, the show is currently airing its twenty-first season and is pretty close to hitting the five hundred episode mark. Impressive, to say the least!

More than any other series on television, Law & Order: Special Victims Unit does a fantastic job of accurately portraying victims of sexual assault and the entire process behind the trials and investigations. But, after so many seasons and countless episodes, how well do you think you know the show? Let's take a look at ten things you probably missed about the main characters!

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Have Your Heard Of John Munch?

Richard Belzer as John Munch in Arrested Development

With the rise of spin-off shows making its way into television, it became quite common for characters to jump from one show to another, making interesting cameos, and connecting several worlds. This mostly happens every once in a while, and it's not very common for a character to be present in more than two, three shows.

Unless, of course, that character is John Munch. Richard Belzer's character has been present in ten different television shows, including  The X-Files, 30 Rock, The Wire, and Arrested Development. Who would've thought it's possible to milk the same character in so many different universes?

The Most Official Voice You'll Ever Hear

The main cast of Law & Order: SVU

There are many things that make Law & Order: Special Victims Unit instantly recognizable. Even if an episode is starting, you can instantly tell what you're watching due to the very uncommon intro of the show, that's also present in the original series and its several spin-offs.

The voice-off is narrated by Steve Zirnkilton. His voice already sounds pretty official and stern as it is, but perhaps the best part of the whole thing is that Steve actually had a career as a politician, serving eight years in Maine's House of Representatives. There's no better way to give your show even more credibility than to bring out an actual insider!

It Isn't All Acting When It Comes To Olivia

Mariska Hargitay has been playing the role of Detective Olivia Benson for over fifteen years now. Playing the role of a person in law enforcement facing cases that, unfortunately, can and do actually happen in real life will eventually catch up to you. Actress Mariska was so moved and affected by all of this that she actually got trained as a rape crisis counselor.

This, of course, only gave an already brilliant performance an extra kick, elevating Detective Olivia from just a hollow character to someone being played by a woman who actually cares about the subject matter of the show.

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Now Ice You, No I Don't

Ice-T as Tutuola on Law & Order: SVU

Ice-T has been around for quite some time on the set of Law & Order: Special Victims Unit, and he often serves as somewhat of comic relief. On a show that deals with the heavy and heartbreaking topics of sexual assault and rape, it's always nice to have characters lending some balance in the form of lightness of heart.

This was actually a very lucky addition since Ice-T was originally hired for only four episodes. However, he definitely managed to make an impression, and one good enough to make sure he became an essential part of the Special Victims Unit. Audiences couldn't be happier, because hey, it's Ice-T, after all!

It's Olivia's Show Now

Mariska Hargitay as Olivia Benson in Law & Order: SVU

As we've mentioned above, Mariska has been playing the role of Olivia Benson for the course of twenty-one seasons. Unlike other characters that came and went or left the show for good, Mariska has only been absent for nine out of four hundred and eighty episodes. That's absolutely incredible!

This actually makes her, according to IMDb, "the longest-serving actress in the same role in the history of American live-action prime-time television". Many perks come with the job of being an actress, but very few in the trade actually get to break records. Mariska deserves it, considering the pivotal role she plays on the show.

Catch The Oscar Performance!

Throughout the course of its many seasons and even more episodes, the show has welcomed its fair share of guest stars. Even television series that don't run for this long often incur in the habit of welcoming quite a few seasoned and popular actors and actresses, so there's no reason Law & Order: Special Victims Unit shouldn't partake in the trend.

As a matter of fact, the show has welcomed heaps and heaps of talent. Many of their guest stars were actually Oscar winners, and these include the likes of Robin Williams, Whoopi Goldberg, Olympia Dukakis, Jeremy Irons, and Bradley Cooper, to name a few. With so much talent sharing a screen, it's no wonder the show gets everyone hooked.

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Is That You, Mother?

Even though there's so much to unpack in the tremendous amount of episodes the show has produced, surprisingly very few episodes actually focus on the real-life of the characters. This is probably due to the fact that the show was made to raise awareness and tell the stories of rape and sexual assault survivors, as opposed to that of the characters.

Mariska took advantage of this fact by paying homage to her real-life mother, Jayne Mansfield. Well, actually, it's Olivia's desk. But that hasn't kept Mariska from having a picture of her mother there!

I Feel Like I've Seen You Before...

Gary Cole in promo from pulled SVU episode

It probably comes a time on a show when you run out of actors to cast. That seems a bit unlikely, but casting processes aren't exactly easy and take up a lot of time and resources, which is why some shows often choose to re-cast actors that have previously been on the show to play different characters.

When it comes to Law & Order: Special Victims Unit, this has happened quite a few times. For instance, Diane Neal played a woman accused of rape before she was again cast as a series regular. Similarly, before she was Detective Amanda Rollins, actress Kelli Giddish played a rape victim during season eight.

Lucky Number Nine

Main casts rarely remain the same throughout the run of the show, especially when it comes to television series that have been going on for so long. Those who have been watching Law & Order: Special Victims Unit since it first premiered probably noticed that this is exactly what happened on the show.

To this date, season nine remains the season with the most cast members in the main team. These include Mariska Hargitay, Christopher Meloni, Richard Belzer, Diane Neal, Ice-T, Adam Beach, BD Wong, Dann Florek, and Tamara Tunie. Curiously enough, the fantastic nine were all together during the ninth season.

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A Patriotic Unit

Joe Biden on Law and Order SVU

You don't choose to be an officer of the law just because! As it happens in real life, becoming a member of the police force, the FBI, and so on, happens because people have a deep desire to do good for people and for their country. What also happens outside of the world of television is that it's very common for members of law enforcement to have served in the army.

In Law & Order: Special Victims Unit, many members of the main team have also served in one way or another. Captain Cragen was in the Green Berets, Detective Stabler was in the Marines, Dr. Warner was in the Air Force, and Detective Tutuola was an Army Ranger. A very patriotic unit, indeed!

NEXT: Law And Order SVU: 10 Biggest Plot Holes From The Past 20 Seasons