Smallville, the 10-year long story of Clark Kent discovering himself before embracing his destiny as Superman, became the first modern comic book series that paved the way for the genre’s expansion today. Hadn’t it been for the Tom Welling-led series, things like the Arrowverse, the Marvel TV shows, and more would probably not have been where they are now. While the series heavily explored Clark’s backstory, it also incorporated several elements from the DC Universe. In the later seasons viewers began to see more appearances of various DC heroes and villains.

Some ended up returning while others only appeared for one episode and nothing more. With a couple being less memorable than others, there was a handful of them that were more than impressive. Even if they didn’t return beyond their one episode, their presence alone made said episode as strong as it was. These are 10 of Smallville’s best DC guest characters who appeared for only one episode.

Dan Turpin

Smallville-Dan-Turpin

Before becoming one of Superman’s closest allies in the police force, Dan Turpin had, unknowingly, teamed up with the future Man of Steel. In the season 8 episode “Bulletproof”, Clark ends up going undercover as a cop who gets partnered with Turpin. As Clark is doing as a story for the Daily Planet, the last son of Krypton gets to see what it’s like to risk your life every day without super-powers.

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Through the eyes of Turpin, Clark gets a valuable lesson that became part of his growing experience before suiting up as Superman. Even though Turpin never came back in the following seasons, his guest spot still remains one of the key points of the episode.

Roulette

Roulette in Smallville

The show’s Green Arrow had a spiral down in the ninth season after the events of season eight. As things began to get darker for Oliver, his super-friends eventually got him out of it, but through extreme methods. This is where the DC character Roulette entered the picture as she was hired to put Oliver through a trial that would make him see that he is and always was meant to be a hero. It’s one of the more intense episodes of season 9 and Roulette is one of the main reasons for that.

Bruno Mannheim

Smallville-Bruno-Mannheim

One of Superman’s street-level foes from the comics is the loud-mouthed Bruno Mannheim. The Intergang-associated character showed up for the 19th episode of Smallville’s eighth season when Lois was posing as short-lived heroine Stiletto. While Bruno’s connections to Intergang were nowhere to be seen, he still made for a decent villain-of-the-week.

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His rude behavior and short temper made it easy to love to hate Bruno instantly. While he managed to shoot Clark while under the effects of Kryptonite, Jimmy gets to take him down to a satisfying level.

Saturn Girl

Smallville-Saturn-Girl

In the eighth season of the series, DC Comics writer Geoff Johns began an annual tradition that lasted into the final season. Each season when he was guest-writing, Johns would introduce a big element from the DC Universe and for his first episode he brought in the Legion of Super-Heroes. While Cosmic Boy would return for a second time following this episode, that wasn’t the case for the other two heroes. One of them was Imra Ardeen a.k.a. Saturn Girl who, despite her one-time appearance, became one of the better heroines to enter the Smallville universe.

Lightning Lad

Just like Saturn Girl, Garth Ranzz a.k.a. Lightning Lad was the other member to not return after the team’s introduction episode. While Imra served as the calm force of the trio, Garth was the nerd that many viewers could probably relate to.

From his meta-comments about Clark still not being in a suit to the Boy of Steel’s lack of flying, Garth was a comedic presence that was needed at that time. Seeing him constantly looking up to the future Superman was another reason why Johns’ first episode was such a success.

Zan

Smallville-Zan

In the ninth season, the writers decided to bring a pair of DC characters that fans were probably not expecting to see: the Wonder Twins. Despite being some of the cheekier heroes of the DC Universe, the Smallville spin on them ended up being way better than expected. One half is Zan, the wild card out of the two siblings as his intentions to be a hero like the Blur didn’t go exactly as he had hoped. But by the end of the episode, Zan already showed massive growth after having gotten to save Metropolis’ guardian angel.

Jayna

Smallville-Jayna

Without Jayna, there is no Zan just like there is no Zan without Jayna, the other Wonder Twin. Similarly to her brother, Jayna was all about trying to be a hero like the Blur. Although it was eluded that out of the two, she was the slightly more responsible one. Just like Zan, Jayna was also adapted incredibly well.

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Even though they’re never seen again in the series, their story does get to continue in the Season 11 tie-in comic. In one of the side-stories that they’re featured in, Zan and Jayna have become members of the Teen Titans.

Superboy

Superboy in Smallville

While he technically appeared in multiple episodes in the final season, Connor Kent officially made his debut in the 16th episode “Scion.” Starting out as Alexander Luthor, the clone of Lex and Clark, he eventually went through a metamorphosis-type of change. As he had forgotten the evil deeds he had committed as Alexander, the clone ended up going by Conner later on. Once he discovers his origin, Conner makes his decision by choosing to be a Kent rather than a Luthor. Even though he doesn’t get named Superboy until his Season 11 arc, Conner did get to sport his iconic shirt before the episode ended. The fact that Smallville even got to introduce Superboy before Clark had become Superman was a major deal, especially for being in the final season.

Doctor Fate

Dr Fate in Smallville

Johns’ second episode became an even bigger deal when he was introducing the Justice Society of America. But his plan was so ambitious that it turned into a two-parter dubbed Absolute Justice. One of the three JSA members he got to introduce was Doctor Fate, one of the most iconic magic-based characters in DC. From his first scene to the moment when he was brutally murdered, Kent Nelson was a refreshing addition. His presence was so pivotal that it made Kent’s death that more frustrating.

Booster Gold

Booster Gold in his costume on Smallville

For Johns’ final episode of Smallville in season 10, he introduced Michael Jon Carter a.k.a. Booster Gold. Even though he was only there for one episode, the show’s interpretation of Booster was spot on and made you want more of him. While starting out as the bragging hero he is known to be, Booster gets a valuable lesson or two from Clark before he officially became Superman. That’s what helped him, in the end, to save Jaime Reyes from an out-of-control-Blue Beetle as this was the teen hero’s debut episode as well.

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