Law & Order: 30 Best Guest Stars

Sarah Paulson earned her very first on-screen credit thanks to one 1994 episode of Law and Order. She played a 14-year-old girl named Maggie Conner, who is being investigated for the murder of her mother.

After appearing in a short film in 2000, Ginnifer Goodwin joined Law & Order for one 2001 episode. Then a relatively unknown actress, Goodwin played a young woman named Erica.

Years before she made it to jail as Orange Is the New Black's Sophia Burset, Laverne Cox picked up an early role as Minnie on Law & Order.

Sarah Hyland was just 13 when she appeared on Law & Order. The young actress played Kristine McLean in a 2004 episode.

Before he was starring in Luther and earning critical acclaim for his big-screen work, Idris Elba was filling his résumé with smaller roles, such as an appearance in a 2001 episode of Law & Order.

Philip Seymour Hoffman landed his first credited gig with a 1991 episode of Law & Order. The late star played Steven Hanauer, a man facing trial in a rape case.

Before Scandal, Django Unchained, or even Ray, there was Law & Order. Early in her career, Kerry Washington appeared in one 2001 episode of the crime show, playing Allie Lawrence.

Joining the list of newbies who debuted on Law & Order, Leighton Meester picked up her first on-screen credit thanks to a 1999 episode. She played a young woman named Alyssa Turner.

After making brief appearances in TV movies and episodes of Swift Justice and Dead Man's Walk, Jennifer Garner joined Law & Order for one 1996 installment. She played Jaime, a graduate student.

Julianna Margulies nabbed the second on-screen credit of her career thanks to Law & Order. After appearing in Out for Justice, she popped up in a 1993 episode of the show as Ruth Mendoza, a Navy lieutenant.

After debuting in a short film, Claire Danes hit the small screen for the first time in 1992, appearing in an episode of Law & Order as Tracy Brandt.

Early in his career, Josh Radnor joined Law & Order for one 2002 episode. The future star played a man named Robert Kitson.

Before the boys of Dream Street dropped their first album, Jesse McCartney landed his second acting credit for an episode of Law & Order. The actor and singer appeared on the show in 2000, playing Danny Driscoll.

Kate Walsh hit the small screen for one of the first times in 1997, playing Kirstin Blair, a Navy lieutenant under investigation, in Law & Order.

Years before she made it to the White House as The West Wing's C.J. Cregg, Allison Janney was on Law & Order for two episodes. She played Nora in a 1992 installment and Ann Madsen in 1994.

Zoe Saldana continued the tradition of debuting on Law & Order, playing a woman named Belinca in 1999. She is pictured here with Orange Is the New Black star Selenis Leyva.

Years before Primal Fear, The Truman Show, or Love Actually, Laura Linney appeared on Law & Order. The actress was featured in one 1994 episode as Martha Bowen.

Chris Messina earned his first on-screen credit in 1995 thanks to Law & Order. He played Tommy Bell in his debut role, and would return to the show in 1996 and 2003 as Kevin Turner and Don Cushman, respectively.

Emmy Rossum's first credited acting gig was in a 1997 episode of Law & Order. The young actress played Alison Martin, a girl in a bad situation with her family.

Amanda Peet picked up an early role in one 1995 episode of Law & Order. She played Leslie Harlan, a woman in the midst of a mysterious case.

Sebastian Stan landed his very first on-screen role in 2003. He played Justin Capshaw on Law & Order, a young man who was kidnapped as a boy.

Courtney B. Vance found his way to the courtroom as Johnnie Cochran on The People v. O.J. Simpson: American Crime Story, but more than 20 years earlier, he landed early roles on Law & Order. He had an uncredited part in a 1990 episode and returned in 1995 as Benjamin "Bud" Greer.

Ellen Pompeo's first credited small-screen role was in a 1996 episode of Law & Order, playing Jenna Weber. She returned in 2000 as Laura Kendrick.

Peter Facinelli nabbed his second on-screen gig in 1995, playing Shane Sutter in one episode of Law & Order.

Vera Farmiga added a third title to her résumé in 1998 thanks to Law & Order. She played Lindsay Carson, a woman caught up in a murder trial.

More than a decade before she became Grey's Anatomy's Dr. Miranda Bailey, Chandra Wilson was Serena Price for one 1992 episode of Law & Order.

Ty Burrell became an Emmy nominee in 2010 thanks to Modern Family, but 10 years earlier, he made his small-screen debut on Law & Order. He appeared in a 2000 episode as Paul Donatelli and returned to the show in 2003 as Herman Capshaw.

Edie Falco earned an early credit on Law & Order, appearing on the crime show in 1993 as Sally Bell. She reprised the role for additional turns in 1994, 1997, and 1998.

Early in her career, Felicity Huffman appeared on Law & Order. The actress joined the show for one episode in 1992, playing Diane Perkins, and returned in 1997 as Hillary Colson.

Isaiah Washington landed one of his very first projects as Derek Hardy on Law & Order, appearing on the show in 1991.