Part of what makes Glee such a pleasurable show to watch is the variety of characters that it introduces. While obviously the main cast are the best, there are a number of secondary characters that appear as the series goes on, both men and women who are in their own ways as fascinating, complex and, yes, infuriating, as their primary counterparts. What’s more, they often get their own storylines that help to elaborate on their personalities and their motivations.

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Whether they continued to make appearances throughout the show’s run or whether they only had a few appearances, all of these characters made quite an impression.

Sebastian Smythe - “The First Time”

Sebastian and Blaine

Everyone loves a villain, and Sebastian certainly fits the bill. From the moment that he appears in “The First Time,” he’s something of a nuisance, always scheming against New Directions and, in particular, trying to get Blaine to break up with Kurt and date him. His efforts fail, of course, his deviousness and cunning makes him a compelling character to watch, even as the series clearly wants the viewer to strenuously dislike him.

Blaine Anderson - “Never Been Kissed”

Blaine singing You Should Be Dancing while at class in Glee

Of all of the characters that have appeared on this show, Blaine is one of the best. It was a little unclear when he first appeared in the second season whether he was going to have staying power, but it wasn’t long before he cast his spell, both over Kurt and over the audience. It helps that he’s played by the tremendously charming and charismatic Darren Criss, which imbues this character with genuine warmth, and his relationship with Kurt is one of the best on the series.

Coach Beiste - “Audition”

Coach Sheldon Beiste talking to Will and Sue in the McKinley halls

What’s great about this series is that, while it of course focuses a lot on the young people, it also gives significant attention to the adults, as well. Coach Beiste is one of the better adult characters, in part because his storyline is so compelling and heartwarming, particularly his coming out as trans and his subsequent transitioning. It’s also quite lovely to see the ways in which many of the faculty at the school welcome him into their community (after an admittedly rough start).

Jesse St. James - “Hell-O”

Jonathan Groff as Jesse St James in Glee

Jonathan Groff is another of those actors who just seems to have more charm than any one person should possess, and he brings all of that to bear in the character of Jesse St. James. This is yet another of those characters that is rather morally ambiguous, since he can’t seem to decide whether or not he wants to be with Rachel. Of course, he ultimately loses her to Finn, and one can’t help but wonder what their relationship might have looked like had it worked out.

Shelby Corcoran - ‘Hell-O”

Idina Menzel as Shelby in Glee

It was probably inevitable that theater giant Idina Menzel would appear in this show, especially considering the way that she looks quite a lot like Rachel. In fact, within the series she is revealed to be Rachel’s biological mother.

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While Shelby is one of the less prominent characters on the show, every time she appears on the screen is memorable, particularly the duet form of “Poker Face” that she sings with Rachel (definitely in the top ten performances on the show).

Sam Evans - “Audition”

Given that the main characters introduced in the first season were fated to eventually graduate, it made sense that the show would have to start adding in new characters, and one of the better additions was Sam. He had the sort of blonde good looks that made him an instant crush for many of the series’ younger fans, and it definitely helped that he had a good voice that allowed him to deliver some very catchy and melodious performances.

Lauren Zizes - “Wheels”

Lauren Zizes In Glee

Lauren was another fascinating character. She was one of those take-no-prisoners types, a strong young woman who wasn’t afraid to tell people what she thought of them (a common type of character on this series). While she didn’t stay with New Directions that long (since she felt that it was hurting her standing with the rest of the school), she clearly took a lot of pleasure in it, and it was rather nice to see the relationship that flourished between her and Puck.

Becky Jackson - “Wheels”

Sue and Becky in Glee

If there’s one thing that Ryan Murphy is good at in his shows, it’s in giving those who are typically underrepresented on screen their chance to be stars. Becky Jackson is, hands down, one of the best supporting characters on the show.

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Though she does have Down’s Syndrome and while this is central to her identity, she really is just like other students, and she’s even allowed to be a villain (since she allies herself with Sue Sylvester, the nemesis of New Directions and everything they stand for).

Burt Hummel - “Preggers”

Burt and Carole standing saide by side in Glee.

It would have been very easy to give Kurt Hummel a father who condemned him for his queerness, but that’s thankfully not what audiences got in Burt Hummel. In fact, it’s probably not going too far to say that Burt is one of the best parents to appear on a television series in recent history. He makes it very clear that he loves and supports Kurt, and that no matter what happens he will always be there for his gay son.

Carl Howell - “Britney/Brittany”

What to say about John Stamos? The man is, of course, incredibly handsome, but more than that, he’s also a good actor. In this show, he appears as Carl Howell, a dentist who gets into a relationship with the very nervous and anxious Emma Pillsbury. And, as it turns out, he’s a very good singer, and his performance of “Whatever Happened to Saturday Night” is one of the finest (in an otherwise rather lackluster episode). It’s just a shame that he didn’t last longer on the show.

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