Marvel's Agents of S.H.I.E.L.D. has adapted a surprising number of comic book characters to the small screen over the years. They've successfully taken niche and obscure heroes and villains from the pages of some of our favorite stories and put them into their own narrative.

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There's been some lovable rogues and unforgettable heroes that have graced the show, but unfortunately, none of them last forever. The showrunners are pretty good at fan service and often bring back old characters to tie together the series. With S.H.I.E.L.D. becoming an integral part of the Marvel Cinematic Universe, we take a look at 10 characters we want to see return to the television show and retake their place in the MCU.

10 BLACKOUT

The first villain on this list and one of some recent relevance, Blackout was featured in two episodes in season 1: "Providence" and "The Only Light in the Darkness." He was a compelling foe, hunting the former lover of Agent Coulson after she believed him to be dead.

He possessed comic-accurate powers, with the ability to control the Darkforce. His powers meant he could also absorb energy and use it as a weapon against his enemies. His powers are very similar to others seen in the MCU, including with a later member on this list and in Cloak and DaggerThe actor portraying him has a cameo in Captain Marvel, and it's being ret-conned that it's actually the same character. He's a dangerous threat and a menacing individual that deserves to return.

9 DEATHLOK

Deathlok has had an interesting history with the Agents. He was first a dad and actually featured in the pilot episode of the show. He then was turned into a villain by John Garrett, becoming the cyborg Deathlok. After this, he has a story of redemption and eventually became a hero and a secret member of this stealthy organization.

It's been quite the journey, and the character is a key part of the DNA of the show. There's a certain level of humanity in such a robotic character and he's a lot of fun to have on screen. He's returned many times before and we'd love to see him return again in some capacity, especially since his design is so amazing.

8 ELLIOT RANDOLPH

Perhaps a forgettable character to some, Elliot Randolph is actually an intriguing part of the Agents of S.H.I.E.L.D. family. Randolph is a former Asgardian beserker who decided to stay on Earth after a battle. He's tried to live a normal, human life ever since.

Now that Asgard is destroyed and there is a Midgard version of his home, it would be great to check in on him again, especially since he's so fantastically portrayed by Peter MacNicol. We never got to find out the true identity of the character, with many rumours on which Asgardian he could be. There's also a suggestion that he's an Asgardian version of a comic character called Berserker, especially since a powerful staff was a key part of his story.

7 MADAME MASQUE

This is technically a bit of a cheat pick, but we just love this character so much! Whitney Frost is a well-known Marvel character who has often gone under the name of Madame Masque. She wears a golden mask to hide the terrible scarring on her face.

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She's the villain of season 2 of Agent Carter and was actually left alive at the end of the series after she lost her Darkforce powers. She'd been driven into madness and was constantly trying to claw at her own face, obsessed with her appearance and the thought of being scarred. It would have been great to see where this character went, but the series got canceled. Time travel is now used in the show, so maybe Whitney Frost can carry on in Agents of S.H.I.E.L.D., especially since both series have crossed over before.

6 GRANT WARD

It's difficult to not mention one of the original team members and a key part of the success of the show. Grant Ward has been both a hero and a villain and has returned in many forms, even after his death. It seems fitting that before the series is brought to a close, the character makes one more appearance in a completely different way.

We've already seen a parallel version of Coulson, so why can't we see a similar thing for Ward? Over the years, Ward's alter ego has been speculated on, but we never got to see him become a comic character. The most compelling option was as the Taskmaster, which could work really well with the current narrative.

5 HELLFIRE

A character that's been heavily featured in the show, Hellfire is still kicking around in the MCU. A selfish villain who has the power to control fire and uses a fiery chain as a weapon, the character is both visually interesting and a fun addition to the cast.

His Australian humor and charm, despite his dastardly deeds, make him a great character to bounce off of. He's currently in custody at S.H.I.E.L.D., so if the team ever needs a sort of Thunderbolt of their own, then Hellfire could be a great option to pick. He's previously been a part of the Watchdogs, which were a fascinating group that should also be brought back to cause a bit more trouble.

4 VICTORIA HAND

Yup, believe it or not, Norman Osborn's right-hand woman (no pun intended) was a part of this TV series. She didn't last very long, with the character being shot by Grant Ward when he made his transition to Hydra. It's a real shame, as the character had a lot more to do and had so much potential.

People have been brought back from death before and we hope that Victoria Hand is no different. We want to see that signature purple hair back on our screens soon with her no-nonsense personality. Especially at a time where the organization is rebuilding, having her return in some way could be essential for their success. Or maybe she was a part of Hydra the whole time and her death was faked, which would make her a bigger threat!

3 BLIZZARD

It's really puzzling why we haven't actually seen Blizzard return at all. The villain was given a proper origin story and was cast perfectly with Dylan Minnette, who's a star on the rise. By the end of his appearances, he possessed all the powers that the character does in the comics and had even sided with Hyrda.

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He disappeared and was clearly written with an ending that made sure he would return in some capacity in the future as a much larger threat. However, he just never came back and it's not clear why. Perhaps the actor became too busy or the showrunners didn't know what to do with him. We'd like to see his character fleshed out more, though, as Blizzard deserves better.

2 KRAKEN

It's surprising that this major Hyrda character actually appeared on the show for so long but never got to suit up in his signature Kraken armor. Dr. Whitehall was a Nazi scientist and member of Hydra who lived for much longer than he ever should have been able to, thanks to his experiments on Inhumans.

He was a villain that faced the organization across his lifespan and was eventually shot and killed by Coulson. But Hydra has a way of cheating death, and it would be brilliant if the evil Doctor returned and brought about a new organization as Kraken, finally in his comic accurate costume. He was such a menacing character and could be played off well with Fitz's Doctor.

1 MOCKINGBIRD

It's criminal that Mockingbird hasn't been brought back in some capacity, especially since Hunter came back last season. The character was written out due to ABC developing her own TV show, which was then dropped. She had no way of returning clearly and Bobbi Morse has sat on the shelf ever since.

This is such a shame and a waste of a great hero and a wonderful actress. The showrunners need the right opportunity to employ her skills again, but she really brought the superhero to a superhero show and was a beloved member of the team. Even if she's brought back for just one episode, it would be nice to see what she's up to now!

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