What's the Best 'Law & Order' Series of All Time?

Episodes: 8

Featuring: Edie Falco, Gus Halper, Miles Gaston Villanueva, Anthony Edwards, Josh Charles

The premise: Piggybacking on the instant-nostalgia success of FX's 2016 hit, The People v. O.J. Simpson: American Crime Story, Dick Wolf attempted a splashy limited series of his own, using another trial of the century as its subject matter: the infamous Menéndez Murders case. Based on the real-life 1989 killings of wealthy couple José and Kitty Menéndez by their sons Lyle and Erik. Law & Order: True Crime is a compelling enough legal procedural, and it serves up all the tawdry tabloid sensationalism you could possibly want, but it never feels like a good fit with the Law & Order brand. The real bright spot, though, is Edie Falco as Leslie Abramson, the tough-as-nails defense attorney representing the baby-faced killers.

Best episode: Episode 6

After five hours of dramatic legal buildup, the jury finally hears from Lyle (Miles Gaston Villanueva) and Erik (Gus Halper). As the brothers take the stand, they recount in detail the years of sexual abuse that they argue made them fear for their lives. The dramatic high point of the series, the episode ends on a cliffhanger as the jury is left to determine a verdict. Will they buy the brothers’ testimony or see through it?

Watch it: Episode 6, on Amazon Prime

RELATED: The 15 Best True Crime Shows to Binge Right Now

(Left to right) Freema Agyeman, Ben Daniels, Bill Paterson, Harriet Walter, Bradley Walsh and Jamie Bamber in "Law & Order: UK."

BBC/Courtesy Everett Collection

4. Law & Order: UK

Air date: 2009-2014

Episodes: 53

Featuring: Bradley Walsh, Freema Agyeman, Jamie Bamber, Ben Daniels, Harriet Walter, Bill Patterson

The premise: Think of this one as the original Law & Order but with more fish-and-chips shops and barristers’ wigs. The half cops-half courts formula is a carbon copy of the U.S. version, but the setting makes that old formula feel slightly exotic and fresh. And anyone who's watched an episode of Helen Mirren's Prime Suspect will be familiar with the terminology used by the U.K.'s Metropolitan Police Service. Still, crime is crime, and even on the other side of the pond, there's really nothing new under the sun (or, in this case, under the grey, rainy sky). Bad guys are still up to no good, and it's up to a dedicated group of rumpled cops and stretched-thin prosecutors to put them behind bars. Despite some initial growing pains, the series eventually found its footing and grew into an excellent companion to the other Law & Order series, especially after you got used to the sight of cop cars racing down the wrong side of the street.

Best episode: “Deal,” Season 5, Episode 6

A woman is found shot in her bed. But why? Soon, the police pin the shooting on a 13-year-old boy (Jamie Cummings) whose mother is a crack addict. He tells the sympathetic Detective Sgt. Matt Devlin (Jamie Bamber) that his mother sold him to a local drug kingpin named Mark Ellis (Charles Mnene) in exchange for drugs, and that he was instructed by Ellis to shoot someone else, but he missed. Using the boy to work their way up the criminal food chain, Crown Prosecutors Jacob Thorne (Dominic Rowan) and Alesha Phillips (Freema Agyeman) finally bring Ellis to justice, but the young boy's fate takes a tragic and inevitable turn.

Watch it: "Deal,” on Amazon Prime

(Left to right) Kathryn Erbe as Det. Alexandra Eames, Vincent D'Onofrio as Det. Robert Goren, Jamey Sheridan as Capt. James Deakins and Courtney B. Vance as A.D.A. Ron Carver in "Law & Order: Criminal Intent."

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3. Law & Order: Criminal Intent

Air date: 2001-2011

Episodes: 195

Featuring: Vincent D'Onofrio, Kathryn Erbe, Jamey Sheridan, Courtney B. Vance, Chris Noth, Annabella Sciorra

The premise: Criminal Intent follows the work of the NYPD's Major Case Squad, a group of detectives who specialize in high-profile cases involving VIPs, government officials and the bold-faced rich and powerful types. Less interested in the legal half of the traditional law-and-order equation, the show (at least in the first four seasons) mostly chronicled the cases assigned to Detectives Robert Goren (Vincent D'Onofrio) and Alexandra Eames (Kathryn Erbe) — an odd-couple pairing that matched his tortured and eccentric psychological insights with her more even-keeled, empathetic professionalism. More than any other L&O series, though, Criminal Intent always felt more like a showcase for a single actor (D'Onofrio) than a true ensemble.

Best episode: “Endgame,” Season 6, Episode 21

D'Onofrio's Detective Goren is summoned to speak with Mark Ford Brady, a convicted serial killer on death row (played by Roy Scheider). Brady reveals that there are more victims of his crimes than the police ever knew, leading Goren on the hunt to track down new evidence. Brady also has another secret — that he once had an affair with Goren's ailing mother (Rita Moreno), a twist that turns the case into the most personal and psychologically devastating case Goren has ever tackled.

Watch it: “Endgame,” on Amazon Prime

(Left to right) B.D. Wong as Dr. George Huang, Dann Florek as Capt. Donald Cragen, Michaela McManus as A.D.A. Kim Greylek, Christopher Meloni as Det. Elliot Stabler, Mariska Hargitay as Det. Olivia Benson, Ice-T as Det. Odafin "Fin" Tutuola, Richard Belzer as Det. John Munch and Tamara Tunie as Dr. Melinda Warner in "Law & Order: Special Victims Unit."

Justin Stephens/NBCU Photo Bank/NBCUniversal via Getty Images

2. Law & Order: Special Victims Unit

Air date: 1999 to present

Episodes: 485 and counting

Featuring: Mariska Hargitay, Christopher Meloni, Richard Belzer, Ice-T, Dann Florek, BD Wong

The premise: Well, it's hard to top the show's opening voice-over for an explanation: “In the criminal justice system, sexually based offenses are considered especially heinous. In New York City, the dedicated detectives who investigate these vicious felonies are members of an elite squad known as the Special Victims Unit….” As hard as it might be to believe, the lurid SVU has now cranked out more episodes than the original L&O and is currently the longest-running drama in television history. Mariska Hargitay leads the crackerjack cast as compassionate crusader Detective Olivia Benson alongside Christopher Meloni's seen-it-all Detective Elliot Stabler (until he left the show after Season 12). Working the seediest corners of New York City's underbelly, there's no shortage of fresh horrors for the Special Victims Unit to unearth as its members struggle to hold onto their humanity in the process.

Best episode: “911,” Season 7, Episode 3

About to head out for the evening, Hargitay's Detective Benson receives a call from a distraught girl who says she's locked in a room alone. Is it a prank? Or is she actually the victim of child pornography predator? After Benson draws out her story over the phone, she races into action. But will she get to her before it's too late? “911” is tough stuff. But it's also a gripping race-against-the-clock thriller — and a master class from Hargitay, who won an Emmy for her intense performance in the episode.

Watch it: “911,” on Hulu

(Left to right) Jesse L. Martin as Det. Ed Green, Sam Waterston as Executive A.D.A. Jack McCoy, Jerry Orbach as Det. Lennie Briscoe, S. Epatha Merkerson as Lt. Anita Van Buren and Elisabeth Rohm as A.D.A. Serena Southerlyn in "Law & Order."

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1. Law & Order

Air date: 1990-2010

Episodes: 456

Featuring: Chris Noth, Jerry Orbach, S. Epatha Merkerson, Sam Waterston, Benjamin Bratt, Carey Lowell, Angie Harmon, George Dzundza

The premise: The original — and, hands down, still the greatest — Law & Order is … Law & Order. Sure, police procedurals, from Dragnet to Hawaii Five-O, had been around for ages on TV. But the novel twist of Dick Wolf's hit NBC series was showing not just a bunch of disheveled detectives going about their day-to-day shoe-leather sniffing and sleuthing, but also what happens after they slap the cuffs on their suspects and throw them in the clink. Dividing the show into two “separate but equal” halves, Law & Order revealed how the Manhattan DA's office goes about its job, turning NYPD evidence into a conviction — or not. The two sides often worked hand in hand, but just as often could be at odds. Although the faces on the series changed over the years (we'll always be partial to the Jerry Orbach seasons) and new blood was brought in to spice things up when ratings started to stagnate, Law & Order never lost focus on what it was: the most addictive (and twist-filled) hour of ripped-from-the-headlines TV comfort food of its time.

Best episode: “Pro Se,” Season 6, Episode 21

After three brutal murders are committed at a SoHo clothing store, Detectives Lennie Briscoe (Orbach) and Rey Curtis (Benjamin Bratt) arrest a schizophrenic homeless man (played by the always welcome Denis O'Hare) for the crime. He clearly committed the stabbings. But is he sane enough to be found guilty? What at first seems like an open-and-shut case gets complicated when the suspect insists on mounting his own legal defense against DA Jack McCoy (Sam Waterston).

Watch it: “Pro Se,” on iTunes