5 Famous Actors You Forgot Guest-Starred On Seinfeld

Throughout its nine-season run, "Seinfeld" invited countless guest stars to feature in its episodes — though some of them might not be easy to recall. The famous NBC sitcom left a lasting mark on the comedy genre, surrounding its mainstays Jerry Seinfeld (self), Elaine Benes (Julia Louis-Dreyfus), and George Costanza (Jason Alexander) with interesting and hilarious supporting characters.

Despite appearing in just one or a few episodes of "Seinfeld," the series' guest stars found themselves in unique situations and created laugh-out-loud moments. While plenty of big-name actors took a quick gig on the show, many of these performers weren't well-known at the time and only rose to stardom later on. 

The most famous actors who guest-starred on "Seinfeld" before their careers took off went on to headline other iconic TV series and win awards for their work. As a result, the majority of "Seinfeld" fans have likely forgotten they were ever part of the show.

Six years before Mariska Hargitay began starring as Olivia Benson on "Law & Order: Special Victims Unit," she appeared in "Seinfeld" Season 4, Episode 23. "The Pilot," which aired in 1993, featured Hargitay as Melissa Shannon, a woman auditioning for Jerry's self-titled TV show. Melissa reads for the part of Elaine, though George calls an end to her audition after only a few seconds. 

Hargitay's short "Seinfeld" cameo included some fun banter with Jerry and George, and it falls on the long list of small TV gigs that led up to her "Law & Order: SVU" role. Making matters even more interesting, it's rumored that Hargitay was originally in the running to portray Elaine on "Seinfeld" before Julia Louis-Dreyfus was cast. As one of NBC's most recognizable faces for more than two decades thanks to the "Law & Order" franchise, Hargitay is rarely remembered as a "Seinfeld" guest star.

In 1994, actor and filmmaker Jon Favreau made his first-ever TV appearance as Eric the Clown on "Seinfeld." It might be difficult to remember Favreau's presence in Season 5, Episode 19, given that he wears heavy clown makeup and a rainbow-colored wig almost the entire time. In "The Fire," George hires Eric as entertainment for his girlfriend Robin's (Melanie Chartoff) son's birthday party. 

Eric's hilarious moments involve bickering with George, who insults his clown name. Their beef escalates when a fire breaks out and George pushes Eric out of the way to flee the building. In the end, Favreau's character saves the day by extinguishing the fire. Some might not recall Favreau's single-episode "Seinfeld" role, yet others continue to appreciate his performance as the hot-tempered man side-hustling as a clown. Favreau later rose to fame for his work on Marvel and Star Wars movies, but before that, he showcased his talent on "Seinfeld."

Early in Debra Messing's career, she landed a "Seinfeld" guest role that lasted two episodes. She first showed up in 1996's Season 7, Episode 21 as Beth Lukner, a potential love interest for Jerry. Initially married to her husband David (Cary Elwes) in "The Wait Out," Beth separates from him and starts talking to Jerry. However, she eventually opts to rekindle her relationship with David. 

Messing made her "Seinfeld" return a year later in Season 8, Episode 19, "The Yada Yada." Beth has a new husband now, but Elaine accidentally spoils their plan to adopt a child, which drives them apart. After she begins dating Jerry, Beth reveals her true character when she utters a racist and anti-semitic remark while the two attend Mickey's (Danny Woodburn) wedding. Messing was admittedly worried about the obscene line in her "Seinfeld" guest role, but fans still laugh at the moment that promptly ended Beth and Jerry's romance. Nowadays, TV fans overwhelmingly know Messing as the co-lead of "Will & Grace," which came just two years after her "Seinfeld" debut. 

Courteney Cox briefly played Meryl, one of Jerry's girlfriends, in "Seinfeld" Season 5, Episode 17, which aired the same year she started her career-defining role as Monica on "Friends." The 1994 episode "The Wife" sees Meryl pose as Jerry's wife to use his discount at the dry cleaners. But she breaks things off with Jerry when she finds out he let another woman benefit from his discount.

As the central guest star in "The Wife," Cox had the chance to demonstrate her acting ability right before her popularity skyrocketed with "Friends." Cox had more than a few TV appearances under her belt when her "Seinfeld" episode came out, yet none as significant as the NBC show. In fact, Cox's "Seinfeld" experience informed how she approached her time on "Friends," according to her co-star Lisa Kudrow.

"She was also the one when we were first shooting the pilot would say: 'Listen y'all, I did Seinfeld. They help each other all the time. If you think I could be doing something funnier, tell me ... We need to help each other out,'" Kudrow told the "Fly on the Wall" podcast (per NME). "That set a tone which carried through the whole ten years for us."

It's nearly impossible to see Bob Odenkirk as anyone other than James "Jimmy" McGill, aka Saul Goodman, from "Breaking Bad" and "Better Call Saul." Thus, most fans of the actor's work probably don't know that he guest-starred in "Seinfeld" Season 8, Episode 9 back in 1996. In "The Abstinence," Odenkirk played Elaine's boyfriend Ben. An aspiring doctor, Ben has failed to obtain his medical license three times. So, Elaine practices abstinence with Ben, believing that it will help him finally pass his exam since George made himself smarter with a similar strategy.

Elaine's mind instead grows duller, and as if things couldn't get any more comically unfortunate, Ben breaks up with her after finally becoming a doctor. Odenkirk's short "Seinfeld" stint came 13 years before he first appeared as Saul in "Breaking Bad." Odenkirk hadn't seen "Seinfeld" before appearing on the show, but he had experience writing for comedies like "Saturday Night Live" and "The Ben Stiller Show." Odenkirk's knack for humor both in the writers' room and in front of the camera has made itself known throughout his career, from "Seinfeld" to "Better Call Saul."