Since Law & Order: SVU’s debut in 1999, Mariska Hargitay has portrayed the beloved character of Olivia Benson. Hargitay has portrayed Benson initially as a detective of NYPD’s SVU division, then becoming the captain of the same division in season 21.

RELATED: The 25 Best Episodes of 'Law & Order: Special Victims Unit'

A compassionate advocate for victims, Benson ensures that survivors are treated with care and empathy. Hargitay also portrays Benson with a fierceness who ensures criminals are brought to swift justice. Through her years in the SVU squad room, Benson has seen it all and has had to deal with intense, shocking, and exceptional cases. Hargitay’s performance as Benson has rightfully earned her the title as television’s longest-running detective.

Season 6, Episode 4, "Scavenger"

In the season 6 episode, “Scavenger,” the SVU is tasked with hunting down a serial killer throughout the city who leaves clues on his victims, similar to the Zodiac Killer. Benson and Stabler (Christopher Meloni) are forced to solve riddles and puzzles and eventually discover that the murders are being committed by a copycat of the original ‘RDK’ murders. Benson and Stabler must race against the clock when they discover that the copycat killer has kidnaped one of RDK’s original victims and buried her alive.

In their attempts to catch the serial killer, Benson and Stabler are engaged in an intense, nail-biting game of cat-and-mouse. The clues and riddles left by the killer continually raise the stakes, and the intensity only goes higher when the detectives must find his latest victim before the oxygen tank runs out.

Season 7, Episode 3, "911"

In the season 7 episode, “911,” Benson receives a routed 911 call from a child who the squad is unable to track, leading them to believe that the call is a hoax. Against Captain Cragen’s (Dann Florek) advice and orders, Benson stays on the phone with the little girl, who becomes increasingly lethargic and frightened.

The episode’s increasing tension and pressure to find the missing girl keeps the viewer on the edge of their seat. The episode earned Hargitay an Emmy for her performance and is undoubtedly one of SVU’s best episodes.

Season 9, Episode 9, "Paternity"

In the season 9 episode, “Paternity,” Stabler goes out of town, leaving Benson with his pregnant wife Kathy (Isabel Gillies). Kathy and Benson get into a life-threatening car crash, trapping Kathy in their car, and causing Kathy to go into premature labor. Shaken but undeterred, Benson manages to take back control of the dangerous situation by safely delivering Kathy and Stabler’s baby.

RELATED: TV’s Best Detective Duos of the 21st Century, Ranked

Although the episode ends with Kathy safely in the hospital, the tension is rampant in the scene where Kathy gives birth and subsequently loses consciousness. The episode is full of action, both physically and mentally, and is one of the most memorable SVU episodes.

Season 13, Episode 1, "Scorched Earth"

In the season 13 episode, “Scorched Earth,” Benson finds herself with two new detectives in the squad room, Rollins (Kelli Giddish) and Amaro (Danny Pino), after Stabler’s (and Meloni’s) departure from the SVU following the devastating shootout that occurred in the precinct in the season 12 finale. At the end of the episode, Cragen informs Benson that Stabler has filed his papers and effectively resigned from the SVU.

This episode marked the first episode without Stabler’s presence and sees a surprisingly emotional moment from Benson. Normally a tough, yet compassionate detective, it was difficult to watch Benson quietly sob at the news of her partner’s resignation. It wouldn’t be until the series premiere of Law & Order: Organized Crime that Benson and Stabler would reunite.

Season 15, Episode 1, "Surrender Benson"

In the season 15 episode, “Surrender Benson,” Benson finds the tables turned on her when she is kidnapped by William Lewis (Pablo Schreiber). Arguably one of the worst villains of the show, Lewis forcibly drugs and intoxicates Benson and emotionally, physically, and mentally tortures her. Lewis takes them to a remote cabin in the woods where he continues to taunt her until Benson regains the upper hand where she nearly beats him to death.

RELATED: Children of Celebrities Who Became Famous for Their Own Work

In a stunning turn where Benson normally finds herself as the one consoling victims, she finds herself on the other end fighting for her survival. The episode sees Benson nearly snap and murder Lewis and the trauma the experience inflicts on her.

Season 15, Episode 20, "Beast’s Obsession"

In the season 15 episode, “Beast’s Obsession,” Benson once again finds herself face-to-face with William Lewis. In this episode, Lewis escapes from prison and kidnaps a 12-year-old girl, and contacts Benson to taunt her with the girl’s capture. Benson is nearly sexually assaulted by Lewis when he instead forces her into a game of Russian Roulette. After a couple of intense rounds, Lewis shoots himself in the face, taunting Benson one last time.

This episode raises the stakes double-fold in the saga between Lewis and Benson. Benson’s internal desire to help save the kidnaped girl intertwines her with Lewis once again and nearly costs her life. Lewis's death during the nail-biting game of Russian Roulette only inflicts more trauma on Benson’s psyche, rather than bringing her peace and closure.

NEXT: Ranking The 15 Law & Order: SVU ADAs