In the criminal justice system, guest appearances on Law & Order are considered mandatory, with pretty much anyone who is anyone (and Chevy Chase) featuring on the series down the years.

Sometimes actors popped up on the procedural franchise prior to hitting the big time. On other occasions, the powers-that-be were able to convince a notable star to appear on the show, usually as either the villain-of-the-week, or as a teary-eyed victim/witness. Sometimes they were both. In any case, when you saw a big name in those opening credits you knew you are in for some A-lister grandstanding in an interrogation room or court scene.

From the straight-down-the-line Law & Order, to the more intelligent Law & Order: Criminal Intent and the flat-out, balls-to-the-wall bonkers of Law & Order: Special Victims Unit, each incarnation of the show brings its own distinct flavour to the table and some memorable guest stars to boot.

Or at least they should be memorable. The fact of the matter is that there are well over 1,000 episodes and counting of those three shows and that’s not even including all those other short-lived spin-offs (Law & Order: LA anyone?).

Thankfully, someone has taken the time to watch as many episodes as humanly possible (you’re welcome) to bring you the definitive list of 18 Huge Stars You Completely Forgot Appeared On Law & Order. These are their stories (dun dun).

18. Rooney Mara

While Kate Mara seemed happy enough to appear in Law & Order and Law & Order: Special Victims Unit, her sister was apparently left none too pleased by her guest role in the latter.

The elder Mara played Jessica DeLay, in the 2006 episode “Fat”, describing the role and episode in general as “so stupid” in an interview with Allure. “Me and my boyfriend — although I [didn’t] look old enough to have a boyfriend — went and beat up these fat people, and at the end of the show you find out that I used to be obese and I hate fat people. It’s ridiculous. Who would ever do that? Who would beat someone up because they’re fat?”

Mara went on to clarify her comments to The Huffington Post. “If anything, I didn’t mean that the storyline was ridiculous; I meant that humanity is ridiculous,” she said. Whatever you say, Rooney.

17. Julia Roberts

The Pretty Woman star made a guest appearance in a very special episode of Law & Order from the show’s ninth season. When a millionaire dies days after investing in a new sports stadium, a construction entrepreneur emerges as the prime suspect with the victim found to have died as a result of the after-effects of a “performance” enhancing drug.

Roberts plays professional fund-raiser Katrina Ludlow, who steps forward claiming to have uncovered evidence pointing to the killer. There’s just one problem: she’ll only deliver the evidence to detective Rey Curtis (Benjamin Bratt) in a unique and unlikely scenario that creates its own problems– this is Law & Order, after all.

Roberts actually won an Emmy for her performance and dated Bratt for the next three years before the pair split in 2001.

16. Zoe Saldana

The Avatar and Guardians of the Galaxy actress Zoe Saldana popped up in the fifth season episode of Law & Order: Special Victims Unit “Criminal” as the daughter of Javier Vega, a one-time heroin addict and murderer turned reformed character.

Having discovered that he had a daughter, Gabrielle (Saldana), Javier got clean and turned his life around to the point where he was working as a teacher when one of his students – who also happened to be his fiancée – was murdered.

Gabrielle insists he is innocent, though, claiming that he has been set up by someone else. Captain Cragen (Dann Florek) has other ideas, having let Javier off a lesser crime prior to his initial murder all those years ago. Will Gabrielle be able to help her father clear his name? Take a wild guess…

15. Robin Williams

The late, great comedian and actor earned an Emmy nomination for his fine turn in the season nine episode of Law & Order: Special Victims Unit “Authority” – and with good reason too.

Williams played Merritt Rook, a sound engineer and anti-authoritarian criminal mastermind, in one of the most intriguing episodes of SVU to date. Driven to the brink of insanity by the deaths of his wife and unborn child, Rook wages a one-man war that begins with a series of phone calls to a local burger chain.

Posing as Officer Milgram, he is able to convince the restaurant’s manager to conduct an illegal strip-search on an employee he accuses of stealing. It all gets pretty crazy from there. It’s just a shame that Williams’ death means there’s no chance of a follow-up.

14. Jessica Chastain

In less than a decade, Jessica Chastain has been able to carve out a pretty formidable career as an actress starring in some of the biggest and best movies today. Zero Dark Thirty, Interstellar, The Martian, Crimson Peak – when it comes to movies, Chastain knows how to pick them.

The same can’t be said for her choice of Law & Order spin-offs though. Chastain probably thought she had landed on her feet when she was cast in a recurring role as Assistant District Attorney Sigrun Borg on Law & Order: Trial by Jury.

After guest spots on shows like ER and Veronica Mars, this was a chance to earn a steady paycheck for a few occasional appearances. Unfortunately for Chastain, the series lasted just 13 episodes before cancellation, though it’s early demise did at least pave the way for much of the success she has enjoyed since.

13. Elizabeth Banks

Around the same time when she appeared in the very first Wet Hot American Summer movie, Elizabeth Banks also hit the big time as the guest star on this doozy of an episode from the third season of Law & Order: Special Victims Unit.

She played Jaina Jansen, the wife of Wesley – played by Saved By The Bell alumni Mark-Paul Gosselaar – a man found shot and assaulted outside of a gay club. It soon becomes apparent to Detectives Benson and Stabler that the couple have been working in adult movies to pay for their daughter’s treatment for cystic fibrosis.

Things then take a turn when producer Cal Oman is found murdered. All the fingers point to Wesley, following his assault, but most hardcore Law & Order fans know better than that.

12. John Krasinski

A year before he made his name giving glib sideways glances as Jim Halpert on The Office, Law & Order fans were treated to another side of John Krasinski– a more murderous, psychopathic side.

In another of the more unusual episodes of Law & Order: Criminal Intent, Krasinski played Jace Gleesing, a violent high school basketball player who Vincent D’Onofrio’s Robert Goren suspects of killing a private investigator for altogether bizarre motives related to court time.

“Mad Hops” represents a major departure from the friendly, playful, nice guy persona Krasinski would cultivate on The Office. Gleesing is violent to his teammates, deals drugs, and may even be guilty of murder. Watching the episode now, you half expect him to give a knowing wink to camera.

11. Sam Rockwell

Long before he established himself as one of Hollywood’s more interesting leading men via a series of low-key early 2000s crime capers, Rockwell was a jobbing actor with minor roles in movies like Teenage Mutant Ninja Turtles (in the memorable role of “Head Thug”).

What most fans probably forget, however, is that he also popped up in the third season of Law & Order. Entitled “Manhood”, the episode followed the investigation into the death of a police officer and the discovery that three of his fellow officers delayed coming to his aid because he was gay.

Rockwell played one of the guilty trio, Officer Weddeker, who ends up folding like a cheap deck chair and confessing to the crimes after a tense interrogation scene. Despite this, all three are eventually acquitted. This was 1993, after all.

10. Bradley Cooper

Bradley Cooper doubled down on the bad guy persona he first cultivated in the movie The Wedding Crashers with this memorable turn as psychotic lawyer Jason Whitaker, who comes under the gaze of the Law & Order gang after emerging as the prime suspect in a series of rapes.

Cooper’s guest appearance is notable for the fact that it came as part of a crossover which saw his story start on Law & Order: Special Victims Unit before continuing on the short-lived spin-off Law & Order: Trial By Jury.

Cooper is on particularly creepy form as Whitaker, who will stop at nothing to keep his decade-long crimes a secret, helped by his wealthy and overbearing mother – a standard Law & Order trope wheeled out on several occasions down the years.

9. Amanda Seyfried

Amanda Seyfried had already starred alongside Lindsay Lohan in the hit comedy Mean Girls by the time she popped up on Law & Order: Special Victims Unit.

She showed herself to be far removed from her ditzy character Karen Smith though with an intelligent and emotionally charged performance in the episode “Outcry”. Seyfried played Tandi McCain, a teenage girl found beaten and duct-taped under a bench in a newly-constructed dormitory.

Though she initially accuses three army cadets of raping her, the usual Law & Order: SVU story, full of absurd twists and turns begins to play out. By the end, we discover it was, in fact, her stepfather’s boss. They go to court, however, and he gets off scot-free. There’s still time for one more twist though – another victim comes forward.

8. Samuel L. Jackson

Samuel L. Jackson appeared in a glut of major movies before hitting it big with Pulp Fiction so it shouldn’t come as a massive surprise to learn he popped up in the very first series of Law & Order.

Jackson played Louis Taggert, the lawyer at the centre of the episode, “The Violence Of Summer”, in which a television news reporter is gang raped by three defendants (including a fellow pre-fame Philip Seymour Hoffman).

Airing way back in February 1991– putting it somewhere between Jackson’s blink-and-you’ll-miss-it turn in Goodfellas and his cigarette-puffing performance as Ray Arnold in Jurassic Park– the part gave Jackson plenty of opportunity to showcase his talents, with a few memorable moments of interrogation room grandstanding.

Well, it is Law & Order after all…

7. William H. Macy

William H. Macy actually lost his Law & Order virginity in the very first episode of the show, playing Assistant US Attorney John McCormack in the original pilot episode Everybody’s Favourite Bagman.

It wasn’t a particularly memorable turn, with the actor actually credited as W.H. Macy. Thankfully, he would get another shot at making an impression in the show’s second season and, boy, he did not disappoint.

The episode “Sisters of Mercy” saw Macy take on the role of Jack Powell, the unassuming director of a teen shelter suspected of multiple instances of abuse against those in his care.

It’s a dream gig for Macy, who displays the kind of modest menace that he would go on to perfect with performances in movies like Fargo. It’s definitely an episode to seek out if you haven’t already seen it.

6. Viola Davis

Long before she bagged an Oscar for Fences or emerged as the star of her very own crime drama series How To Get Away With Murder, Viola Davis was a jobbing actor doing the rounds on Law & Order: Special Victims Unit.

Davis played the recurring character Donna Emmett, the defense attorney who had the misfortune of defending some of the show’s most despicable villains, while going up against the Manhattan District Attorney’s Office.

It was a thankless task in more ways than one– Davis rarely got a chance to do much other than look po-faced alongside her clients while offering up the flimsiest of arguments in court. She does at least hold the distinction of having appeared in both SVU and Law & Order: Criminal Intent, popping up as Emmett in the episode Badge.

5. Stephen Colbert

He may be the King of delivering Donald Trump-led monologues on Late Night, but there was a time when Stephen Colbert was just another actor trying to get by. Back in 2004, he appeared in Law & Order: Criminal Intent as James Bennett, a counterfeiter whose unjust actions come close to destroying a Catholic charity.

Cast as a kind of everyman version of Norman Bates from Psycho, who is way too close to his mother, the character is supposedly based on Mark Hofmann, a real-life forger who landed himself in hot water after apparently forging historical documents linked to the Mormon faith and Church of Latter Day Saints.

This episode offers a unique opportunity to see a different side to Colbert’s more familiar repertoire. It turns out that he can be a scary guy.

4. Julianna Margulies

Chris Noth and Julianna Margulies would go on to enjoy a seriously twisted relationship on The Good Wife but their first on-screen encounter occurred decades earlier on the Naval-themed Law & Order season three episode “Conduct Unbecoming”.

Margulies played Lieutenant Ruth Mendoza, the key witness in the murder of a female Naval officer at a party. It’s down to Noth’s Detective Logan, alongside Briscoe, to try and discover the truth while the Navy does its best to cover up the crime and protect the killer.

The appearance is notable for being only Margulies’ second ever credited role, with her character Mendoza proving to be the weak link in the Navy’s cover up of the crime. A year after the episode aired, in 1993, she would land a starring role on the hit medical drama ER.

3. Philip Seymour Hoffman

Fifteen years before bagging himself an Oscar, and a whole year prior to his role as Chris O’Donnell’s wimpy prep school antagonist in The Scent of a Woman, Philip Seymour Hoffman did his time on Law & Order.

He played one of three young men accused of the gang rape of a TV news reporter in another harrowing episode of the crime procedural show. The episode, titled “The Violence of Summer”, is notable for being one of the first to put the “Order” before the “Law” (the charges against the trio are temporarily dismissed due to a lack of evidence at the start of the episode, sending the gang back on the case).

It also represents Hoffman’s screen debut (he’s credited as Philip Hoffman) and features another pre-fame appearance from none other than Samuel L. Jackson.

2. Sebastian Stan

A virtually unrecognizable Sebastian Stan took centre stage in the season 13’s Law & Order episode “Sheltered”. Continuing the show’s trait for creating stories “ripped from the headlines,” this episode took inspiration from DC sniper Lee Boyd Malvo.

In the episode, Stan played Justin Lafferty, a young man brainwashed to kill as a “soldier” by a deranged widower and an ex-marksman who kidnapped him from his parents as a five-year-old boy.

When his crazed ex-military captor, Herman Capshaw, loses his job with a construction company, Lafferty takes the only logical step to remedy the situation: he embarks on a sniper rifle-led rampage that leaves four dead. However, in true Law & Order fashion, not everything is as it seems.

1. Claire Danes

Two years before her breakthrough performance as Angela Chase in the angsty teen drama My So-Called Life, Claire Danes featured in a classic bait-and-switch episode of Law & Order from the show’s third season.

The episode “Skin Deep” saw detectives Logan and Cerreta investigating the death of a fashion photographer. Soon enough, they discover the victim’s work is merely a front for a far seedier business.

DNA evidence soon indicates that adivorced mom by the name of Angela Brandt is the likely murderer, with test results suggesting there is an 80 percent chance that she is the killer.

She just so happens to have a teenage daughter, Tracy, played by Claire Danes. If you still can’t see the twist coming, you clearly haven’t been watching enough Law & Order.


Did we forget any other famous stars who have appeared on Law & Order? Have your say on some of your favorites in the comment box!