Comic Book Characters Who Made Their First Appearance on Screen

Harley Quinn – Batman: The Animated Series (1992)

Some side characters are meant to fade away, but Harley Quinn had other plans. Introduced as Joker’s henchwoman in the animated series, she stole the spotlight with her mix of humor, menace, and unpredictable energy. What started as a one-off gag quickly turned into one of the most beloved characters in the Batman mythos. Fans were drawn to her backstory as Dr. Harleen Quinzel, the brilliant psychiatrist who fell for the wrong patient. Harley’s journey from loyal sidekick to independent antihero is proof that sometimes lightning strikes on TV before it hits the comics. She’s now one of DC’s most recognizable icons, all thanks to her small-screen debut. | © Warner Bros.

Phil Coulson – Iron Man (2008)

A character who wasn’t supposed to matter much ended up shaping an entire cinematic universe. That’s Phil Coulson in Iron Man, the quiet S.H.I.E.L.D. agent who shows up to poke around Tony Stark’s chaos. His charm wasn’t in flashy powers or elaborate costumes, but in his dry wit and steady presence. Before long, Coulson became the connective tissue across multiple Marvel films, giving audiences a familiar face to latch onto. It’s rare for a supporting character created for the screen to leap into comics, but he managed it with ease. The MCU’s heart grew bigger because of him, and all from one small but unforgettable debut. | © Marvel Studios

Terry McGinnis – Batman Beyond (1999)

When Gotham needed a new Dark Knight, the comics didn’t hand one over – the screen did. Terry McGinnis stepped into the batsuit with Bruce Wayne as his reluctant mentor, creating a whole new flavor of Batman. Unlike Bruce, Terry was a teenager with impulsive instincts, juggling high school drama with saving a futuristic city. The tension between his youth and the weight of the cowl gave Batman Beyond its spark. Viewers loved how the show wasn’t afraid to be darker, bolder, and weirder than Saturday morning cartoons usually dared. Terry’s origin on television cemented him as one of the most successful screen-born heroes. | © Warner Bros.

John Diggle – Arrow (2012)

In the early episodes of Arrow, John Diggle seemed like just another bodyguard. But the writers clearly knew they had something more, because he quickly became Oliver Queen’s conscience, partner, and brother-in-arms. His military background gave the show grit, while his humanity balanced Oliver’s brooding isolation. Fans embraced him so fully that comics later brought him into their continuity, reversing the usual pipeline. It’s a rare case where a TV-only invention feels like he always belonged in the larger DC universe. Diggle’s role proved that sometimes the most grounded character can be the heart of the story. | © Warner Bros.

X-23 – X-Men: Evolution (2000)

Not every clone gets to break free of their template, but Laura Kinney did it in spectacular fashion. Introduced in X-Men: Evolution, she arrived as a genetic copy of Wolverine with twice the claws and a fraction of the stability. What could have been a gimmick instead became a layered story about identity, trauma, and choosing your own path. Viewers were hooked by her struggle to reconcile being both weapon and person, something no one her age should ever face. The popularity of her animated debut carried her into comics, games, and even film, where she carved her own legacy. From experiment to icon, X-23 showed that originality can thrive outside the panels first. | © Marvel

Chloe Sullivan – Smallville (2001)

Before Smallville, there was no Chloe Sullivan waiting in the comics to be adapted – she was created just for Clark Kent’s teenage years on screen. Smart, fearless, and endlessly curious, she became the friend who always suspected there was more to Clark than he let on. Her Wall of Weird obsession made her the show’s detective figure, unearthing secrets in a town full of them. Fans loved that Chloe was both relatable and ahead of her time, especially in how she embodied internet-age reporting. Her popularity eventually pulled her into the comics, proving she had staying power beyond TV. Sometimes, it takes a brand-new character to make a classic hero shine brighter. | © Warner Bros.

The Wonder Twins – The All-New Super Friends Hour (1977)

No one can capture Saturday morning cartoon energy quite like Zan and Jayna. The Wonder Twins were original creations for The All-New Super Friends Hour, complete with their shape-shifting powers and that unforgettable cry of “Wonder Twin powers, activate!” Sure, one could turn into an animal while the other became water in its many forms – not the most balanced power set, but definitely memorable. Their campy charm became iconic, inspiring parodies, cameos, and eventually full comic book adventures. They proved that even goofy concepts could find a permanent home in superhero lore. The twins remind us that sometimes earnestness beats cynicism every time. | © Hanna-Barbera Productions

Bebop and Rocksteady – Teenage Mutant Ninja Turtles (1987)

Every great hero team needs villains who are equal parts menacing and ridiculous, and Bebop and Rocksteady fit the bill. Debuting in the 1987 TMNT cartoon, these two henchmen were created to give the Turtles more colorful foes than Shredder alone. A mutated warthog and rhino, they were clumsy, loud, and often hilariously incompetent – yet somehow always a genuine threat. Kids loved them because they added both danger and comic relief, making battles unpredictable. Their animated origins didn’t stop them from becoming permanent fixtures in toys, comics, and video games. For villains born out of slapstick chaos, their legacy is surprisingly strong. | © Fred Wolf Films

Morph – X-Men: The Animated Series (1992)

X-Men comics have a huge roster, but X-Men: The Animated Series gave fans someone new to root for – and cry over. Morph started as a fun, lighthearted teammate, using his shape-shifting powers to keep things lively. That’s exactly why his shocking death in the very first episodes hit so hard, setting the tone for a show unafraid of darker stakes. His eventual return, twisted and tragic, only deepened his impact on fans. The fact that a cartoon-original character could inspire such strong reactions says everything about his resonance. Morph’s journey from comic relief to tragic antihero remains one of the show’s boldest moves. | © Marvel Productions

Firestar – Spider-Man and His Amazing Friends (1981)

When the creators couldn’t use Human Torch for licensing reasons, they decided to invent someone brand-new – and thus Firestar was born. Paired with Spider-Man and Iceman, she brought fiery energy (literally and figuratively) to the team. What made her stand out was how well she meshed with the group dynamic, holding her own in both action and personality. Fans connected with her immediately, leading Marvel to pull her into the comics soon after. Over time, she evolved from cartoon invention to respected Avenger, showing just how far a screen-born hero can go. Firestar proves that limitations sometimes spark the best ideas. | © Marvel Productions