The Ryan Murphy empire is on a hot streak with the latest seasons of American Crime Story and Pose, garnering numerous accolades including MJ Rodriguez's Glee.

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For six seasons, the of William McKinley's glee club encountered a colorful cast of eclectic personalities. As the show grew, so did the stature of the guest stars. A-List celebrities would pop in sporadically as either minor cameos or the focal point of an entire episode.

Barry Jeffries and Tim Stanwick - "The Rocky Horror Glee Show"

Barry Jeffries and Tim Stanwick looking serious in Glee

In "The Rocky Horror Glee Show," The Rocky Horror Picture Show alums Meat Loaf and Barry Bostwick play Barry Jeffries and Tim Stanwick, a pair of tv news station managers who recruit Sue Sylvester to disrupt the glee club's production of Rocky Horror.

The duo's bumbling sinisterness is a highlight as the Rocky Horror stars make the most of their short screen time. Glee's brisk tempo, biting wit, and over-blown exaggeration is perfectly encapsulated in any interaction with Sue, and the station managers match her every move. Barry and Tim's obsessive fear-mongering has aged into a sign of what's to come in the real world. And if Glee's sense of humor half can be summed up in line, it's Tim warning Sue of "Mexican Terrorist Ants."

James Lipton - "Goodbye"

James Lipton on an empty auditorium in Glee

The third season finale follows New Direction's first batch of graduates as they tie up loose ends and chart their path into adulthood. As Finn's inner monologue lays out his post-graduation plans, the episode cuts to Finn's audition with James Lipton at the Actor's Studio.

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In the briefest of cameos, Lipton plays himself and is such a pure ray of delight that it is impossible not to smile when he is on screen. Additionally, it is one of the first moments where the show questions if these kids are in over their heads with their dreams of stardom. As someone who mentored actors throughout his career, it's a nice touch to see Lipton point Finn in the right direction.

Nancy Abrams - "Wonder-ful"

Artie and Nancy talking in Glee

In "Wonder-ful", Artie is hesitant to consider moving to New York City for college and leaving his mother by herself. In her short scene, Katy Sagal's Nancy Abrams evokes the loving warmth of a mama bear buttoned up with a biting barb.

Of all of the giant names recruited to play parental figures - Jeff Goldblum, Ken Jeong, Jennifer Coolidge, Gloria Estefan - Nancy is the only one to get a plotline dedicated to the parent-child relationship. For Artie, one of Glee's many ignored characters, Nancy provides a chance to explore one of the kids outside of their dreams and romances. By confiding in his mom, Artie unveils a tenderness and innocence rarely depicted in the show.

Lindsay Lohan - "Nationals"

Lindsay Lohan looking shocked in Glee

Glee's show choir judges fall into two camps: over-the-top characters straight out of a Christopher Guest mockumentary (Kathy Griffin, Anna Camp) or fictional caricatures of celebrities (Marlee Matlin, Jackée Harry). The most memorable judge was 2000s teen icon Lindsay Lohan serving as a judge at the New Direction's second visit to Nationals.

Playing herself, Lohan fit perfectly into the show's swift pace and cartoonish tone as she tossed one-liners at her fellow judges. Of all the celebrity judge cameos, the Lindsay Lohan cameo sticks out the most for the satirical commentary on celebrity comeback culture amidst her real-life comeback and Lohan's ability to snap back into a level of absurdity and rapid speed akin to her iconic performance in Mean Girls.

Patti LuPone - "New York"

Rachel meeting Patti LuPone in Glee

Many Broadway faces made trips to Lima, Ohio, but only one legend appeared as herself during New Direction's time in New York City. During a moment in the second season finale, Broadway legend Patti LuPone runs into Rachel and Finn while the couple has a date at Sardi's.

The scene is every theater kid's dream. Rachel drops her Type-A personality and loses all cool as she geeks out in front of Broadway's original Eva Peron. LuPone presents a persona of grace and gravitas which lends a dreamlike quality to her screen time. Here, Rachel is more than just an uptight, diva obsessed with achieving her dreams. We get a glimpse of the little girl whose ion and love of musical theater drive her every decision.

Betty Pillsbury - "I Do"

Betty and Kevin in Glee

Long before winning a Tony for her performance in the 2019 Broadway production of Oklahoma!, Ali Stroker made waves on the talent scouting reality series The Glee Project. Although she didn't win, Stroker would make a guest appearance in "I Do" as Emma's niece, Betty.

Betty displays grit and confidence that bounce off well with Artie's soft nerdiness. What makes this pairing stand out is that it is one of the few times the show allowed a character to create a relationship with someone outside of the New Directions. Characters switched off love interests so often that it would be quicker to make a list of couples that didn't hook up. This brief fling is a nice change of pace to the show's melodramatic love stories.

David Martinez - "The Spanish Teacher"

David Martinez dancing with Mike and Brittany on Glee

Latin pop sensation Ricky Martin s the glee club as David Martinez, the titular Spanish teacher. "The Spanish Teacher" serves as a showcase for Martin whose charisma shines brighter than his pearly white smile. The episode's highlight is his dazzling duet with Santana of Madonna's "La Isla Bonita".

Related: 10 Glee Musical Numbers That Have Aged Poorly

David's presence finally addresses one of Glee's most glaring plot holes, Will's position as McKinley's Spanish teacher. In doing so, the show humbles Will by introducing someone more qualified and instantly beloved. Will realizes that he has much more to learn and at times must step aside to let someone else lead the way. By the end of the episode, David takes over Spanish classes while Will shifts to the school's history teacher.

Cooper Anderson - "Big Brother"

Cooper looking at Blaine in Glee

Before singing Kelly Clarkson songs in Doom Patrol, audiences were introduced to Matt Bomer's musical abilities in his guest appearance on Glee. Bomer plays Cooper Anderson, Blaine's older, spotlight-stealing brother who everyone falls in love with. Their clashing builds to a confrontation through Gotye's "Somebody That I Used to Know".

A character with a reputation as Mr. Perfect, later seasons see Blaine become one of the more prominent characters with an emphasis on his storylines and solos. Cooper's episode is a rare instance of seeing Blaine as jealous and on edge. He becomes petty and vindictive. It's an interesting layer for a character who, at this point, has only served as a mentor and perfect boyfriend to Kurt.

Britney Spears - "Britney/Brittany"

Britney Spears and Heather Morris in Glee

In "Britney/Brittany," the kids learn to grow through the discography of Britney Spears. With elaborate dream sequences, the episode remakes many of the singer's hit music videos. Each sequence features a cameo from Spears including a memorable meeting between Britney Spears and Heather Morris' Brittany S. Pierce.

Although Glee took every opportunity to skewer celebrity culture with sharp one-liners, this episode is a love letter to Britney Spears and her impact on the show's main demographic. It is a reckoning with the public's perception of Britney Spears long before the #FreeBritney movement made only more tangible with each second of Spears on screen. By having Britney herself approach the kids in their hallucinations, the show brings to life the personal connection between artists and their audience.

Bryan Ryan - "Dream On"

Will and Bryan Ryan sining on stage in Glee

A veteran of Broadway of musicals, Neil Patrick Harris and Glee made a phenomenal pairing. As a school board auditor who peaked during his time in William McKinley's glee club, Harris shines in a role that won him his first Emmy for Outstanding Guest Actor in a Comedy Series.

Bryan Ryan is a textbook example of "keep them wanting more." In one episode, Bryan turns in showstopping performances of Billy Joel's "Piano Man" and Aerosmith's "Dream On" while melding with the show's hyper pace and blunt tone. While characters like Holly Holiday and April Rhodes would go from guest stars to recurring roles, Bryan would never return. It feels like one of the show's greatest calls, to leave perfection alone.

Next: 5 Stars Who Got Their Big Break On Glee