The Marvel Cinematic Universe is the first of its kind, a blueprint for other companies to follow as they try to build their own stitched-together, shared universe on film. Beginning with 2008's Iron Man and continuing up through the recent return of Peter Parker to his Marvel Universe home in Spider-Man: Homecoming, the MCU spans almost a decade's worth of films, involving hundreds of actors in many of them. Some actors draw the lucky straw, and they go on to play easily recognized superheroes -- the mainstays of the Marvel Universe. Others are cast as mere bit players, people to move the action along. And some actors, well you just may have completely forgotten they were even in some of these movies!

RELATED: Made By Marvel: 15 Actors Who Owe Their Careers To The MCU

While many actors like Robert Downey Jr, Gwyneth Paltrow, Samuel L. Jackson, and more have made appearances in a string of MCU movies, acting as the connective tissue between all the disparate stories and keeping the universe as one cohesive whole, many others have only showed up once, or in a cameo, or under heavy makeup. These are the real unsung heroes of the Marvel Cinematic Universe; these are some of the ultimate forgotten MCU actors -- do you remember all, or any, of them?

16 TERRENCE HOWARD

Terrence Howard Iron Man

In the first installment of the Marvel Cinematic Universe, 2008's Iron Man, Terrence Howard brought Lt. Col. James "Rhodey" Rhodes to life for the first time on the big screen. He was a calming and reasonable counterpoint to Robert Downey Jr's brash and impetuous Tony Stark, alongside Gwyneth Paltrow's Pepper Potts. Howard as Rhodes even has a moment during the film's third act where, seeing an unused Iron Man suit, he thinks out loud "...Next time."

The world waited to see what he would bring to the War Machine character in Iron Man 2, but by the time that film rolled around, Rhodey had been recast with Don Cheadle in the role. Howard left the role after a contract dispute, and Cheadle has gone on to play Rhodes to great emotional effect in subsequent films, such as Captain America: Civil War.

15 EDWARD NORTON

Edward Norton as The Hulk

In 2008 the Marvel Cinematic Universe was tearing into the movie theaters, with a one-two punch of Iron Man in April and The Incredible Hulk in June. One of the significant driving forces behind the production of Incredible Hulk was lead actor Edward Norton, the first to step into the tattered purple shorts since Eric Bana's turn in Ang Lee's Hulk earlier in the decade.

Norton signed on for the role of Bruce Banner, and also negotiated the right to several drafts of the screenplay, meaning he would get even more input into the character of the Hulk and the tone of the film overall. The film did reasonably well, but since its release, Norton has exited the franchise, leaving the part to be taken up by Mark Ruffalo, who is clearly having way more fun with it, getting into gladiator fights and all.

14 HUGO WEAVING

Hugo Weaving Red Skull

Weaving is most familiar to our generation as the face of Elrond, who bequeaths the quest on the Fellowship of the Ring, and Agent Smith, the sentient computer virus who desires nothing more than the subjugation of all humanity in The Matrix. You may have forgotten his appearance in Captain America: The First Avenger as the Red Skull due to his extreme prosthetics - -turns out you have to cover a guy in a lot of special effects makeup to create a new skull on top of his old one and paint it fire truck red.

It's also easy to forget Weaving as he's among the unfortunate villains in the Marvel Cinematic Universe who died at the end of the movie without a hope of returning. Plus, given the fact that he was around in the 1940s and the MCU is still in the early 2010s, he'd be ancient at this point.

13 ALEXIS DENISOF

alexis denisof

This one is an easy one to forget -- Denisof, a Whedon favorite after his appearances in Buffy the Vampire Slayer, Angel, and Dollhouse, was cast as Thanos' majordomo The Other in The Avengers, but you'd hardly recognize him under the costume. The Other has an extra thumb on each hand, and wears a cowled robe with a faceplate, leaving only his mouth and red teeth exposed - -surely not the easiest way to recognize Denisof.

While he was a useful character for some expository scenarios in Avengers and Guardians of the Galaxy, he was unceremoniously done away with by Ronan at the beginning of Guardians and in all likelihood will not be returning to grace the MCU stage again. But now who will translate Thanos' many and varied desires for us mere mortals in Avengers: Infinity War?

12 MIGUEL FERRER

Iron Man 3 was a refreshing return to form after the overstuffed mess that was Iron Man 2, and writer/director Shane Black was able to recruit some incredibly strong A-list talent, such as Sir Ben Kingsley and Miguel Ferrer. Ferrer plays Vice President Rodriguez, who is installed by Aldrich Killian as the acting president of the United States when President Ellis is kidnapped, and cooperates with Killian in exchange for Extremis to treat his ailing daughter.

Ferrer came to prominence with his role as OCP Vice President Bob Morton in RoboCop, and he has a long history of appearances in comic book media, mostly as a voiceover actor in DC animated productions. Most recently, he reprised his role as FBI Agent Albert Rosenfield in Twin Peaks: The Return. Sadly, he passed away at the beginning of this year due to complications from throat cancer. He was 61.

11 JEFF BRIDGES

Obadiah Stane Jeff Bridges

Another heavy hitter from Iron Man who never got the chance to make the transition into the rest of the Marvel Cinematic Universe, Jeff Bridges appeared as the Iron Monger, Obadiah Stane. Stane was a friend of Howard Stark's who wanted to steer Stark Industries back to its military-industrial roots and was stymied by Tony Stark's newly awakened conscience. Stane is killed during the third act, when his suit fails in the subzero temperatures of shallow space, and he falls to his death into a failing arc reactor.

Bridges has the distinction of playing the first Marvel Cinematic Universe villain (although a case could be made for the false Mandarin in Tony's Middle Eastern prison), and he created the template for the charismatic, larger-than-life villains required for the superheroes of the Marvel Universe to believably challenge.

10 T.I.

t.i.

Born Clifford Joseph "Tip" Harris Jr, T.I. has had a truly colorful career from all angles. After being dubbed the "Jay-Z of the South" by Pharrell, he went on to a lucrative contract with Atlantic, and once talked a jumper down from a roof while on his way to court to be sentenced to some jail time.

T.I. spoofs his own image as a hardened gangster in Ant-Man as Dave, a member of Scott Lang and Luis's crew in the heist to steal (unknown to them) the Ant-Man suit from Hank Pym. Dave is a laid-back guy, there to have fun and riff on pop culture alongside the rest of the crew, and T.I. brings him to life wonderfully. He is signed on to appear in the sequel, Ant-Man and Wasp, so hopefully we will get even more of Dave come 2018.

9 NATALIE DORMER

Before she became a serious player in Westeros as Lady Margaery Tyrell, Natalie Dormer was an English actress known mostly for her role as Anne Boleyn in Showtime's The Tudors. She has a small part in Captain America: The First Avenger as Lorraine, an English private who attempts to seduce Steve Rogers, even though his true love, Peggy Carter, is standing right there. Rude.

Dormer has gone on to widespread acclaim for her roles as the deadly clever head of House Tyrell, freedom fighter Cressida in the Hunger Games series, and Irene Adler, Sherlock Holmes' love/best friend/archnemesis in Elementary. She also played the part of a doctor in Mass Effect: Andromeda, but she still hasn't been able to get a date with Captain America. But, like, with those abs... can you blame her for trying?

8 GARRETT MORRIS

Known as one of the original cast members of Saturday Night Live, the Not-Ready-For-Primetime-Players, Morris is one of the elder statesmen of modern sketch comedy. With a career that has stood as both beacon and cautionary tale for young black comedians, many of his roles on the show featured him having to use reductive ethnic caricatures.

He has most recently played a supporting role on 2 Broke Girls, a role he began in 2011. His cameo in Ant-Man is very quick (and wordless), playing the driver of the cab Scott Lang lands on just after his first, semi-disastrous Ant-Man test run. He was given the role in honor of his portrayal of Ant-Man in a classic Saturday Night Live sketch with Margot Kidder, "Superhero Party."

7 HARRY DEAN STANTON

We lost Harry Dean Stanton earlier this year, and there has been no other character actor so consistent and so recognizable in the last 40 years. Ever since his appearances in Wim Wenders' Paris, Texas and John Hughes' Pretty in Pink, Stanton was the go-to actor for a character with a hang-dog, worn-down look about them. Stanton's role in the Marvel Cinematic Universe is one of the more fun cameos that isn't a Stan Lee appearance.

When a naked Hulk crashes through the roof of the warehouse he guards and then turns into a naked Mark Ruffalo, Stanton remains generally unfazed, offering some sage advice (and a pair of pants). His cameo was one of many small surprises that made the first Avengers such a charming and fun movie, even if it was about an invasion of murderous alien bug people.

6 LIV TYLER

Liv Tyler looking concerned as Betty Ross in The Incredible Hulk

Liv Tyler is no stranger to big budget disaster movies, with a famous turn as the daughter of oil-miner/astronaut Bruce Willis in Armageddon, and it really helped her settle into her role as Betty Ross, the estranged girlfriend of Bruce Banner in The Incredible Hulk. In this iteration of the Hulk story, Ross is a cellular biologist, inspired and terrified by the cautionary tale of her ex, and Tyler's portrayal is a lot of fun.

Unfortunately, with the fate of future solo Hulk films in question due to distribution issues with Universal, the best we can probably hope for is a cameo or supporting appearance by Tyler in a separate movie -- maybe if we're lucky, we'll get a Betty Ross appearance at the end of Thor: Ragnarok? We can only hope.

5 SETH GREEN

This one was a surprise while we were putting together this list. The mid-credits cutscene in the first Guardians of the Galaxy featured the Collector having a drink with one of his prized "possessions" -- Howard the Duck. That cameo alone launched Howard back into the spotlight, netting a new comic series from Chip Zdarsky and Joe Quinones, and a pretty much guaranteed spot in Guardians of the Galaxy, Vol. 2. What none of us realized at the time was that the voice behind the duck trapped in a world he never made was that it was Robot Chicken's Seth Green.

Green has been doing a lot of voice work recently, as Leonardo on Teenage Mutant Ninja Turtles, Chris Griffin in almost 300 episodes of Family Guy, "Joker" Moreau in the original Mass Effect trilogy, and, you guessed it, Howard the Duck in an episode of the Ultimate Spider-Man cartoon.

4 CHRIS O'DOWD

chris odowd

Chris O'Dowd, the Irish star of The IT Crowd and the love interest in Bridesmaids, appears only once in the Marvel Cinematic Universe -- he has a brief cameo in Thor: The Dark World. O'Dowd appears as one of Jane Foster's ultimately unsuccessful suitors whose date is ruined by the appearance of Darcy with troubling data readings from space.

Both Darcy and Jane believe that the device they are getting readings on is malfunctioning, and as they struggle with it in front of O'Dowd, he channels his Roy character from The IT Crowd to ask if they've tried turning it off and on again. He's credited as Richard in Thor: The Dark World, but who knows -- perhaps it really was Roy, trying to get into dating under a fake name.

3 TOMMY LEE JONES

Tommy Lee Jones is an actor who looks like he'd only be able to star in cowboy movies and post-apocalyptic disaster pieces, but has made a career spanning from films such as Men in Black to No Country for Old Men. He's so talented that he's broken out of the mold, and he can do anything.

In Captain America: The First Avenger, Jones plays the role of Col. Chester Phillips, the military attaché overseeing the Super Soldier program. Phillips is the gruff, world-weary military type that Jones was born to play -- it's a credit to Jones' singular talent that his portrayal in Captain America never feels stale or overplayed. He is the skeptic that Steve Rogers has to overcome to prove himself as a worthy Super Soldier candidate, and the juxtaposition of Chris Evans' naive heroism against Jones' gravelly disbelief is a winning combination.

2 NEAL MCDONOUGH

dum dum dugan

Neal McDonough was once best known to sci-fi fans as Tom Cruise's co-star in Minority Report, but he has since dipped a toe into acting in both the DC Arrowverse of television shows and the Marvel Cinematic Universe. In Captain America: The First Avenger, McDonough appears as Dum-Dum Dugan, an original Howling Commando, and an ally to Captain America once Cap trades in the USO shows for actual field duty.

Dugan went on to a guest starring arc on Agent Carter, but unless the MCU decides to flash back to the '40s and '50s again, we probably won't be seeing him much anymore. If you like McDonough, though, he most recently appeared as Damien Darhk on Arrow, The Flash, and Legends of Tomorrow.

1 HANNIBAL BURESS

Coach-Wilson

This one is still pretty fresh in a lot of people's minds, but Buress's cameo appearances in Spider-Man: Homecoming were both blink-and-you'll-miss-them affairs. In his role as Peter Parker's gym teacher at a school for students who are all strenuously studying science and mathematics, Buress's laid-back style fits perfectly.

He appears in one scene to introduce a video about physical fitness by Captain America, even though he can't remember if Cap is a war criminal or not, and then appears later in the ultimate gym teacher role: the detention supervisor who wants to be there just as little as the kids who have detention. Buress helps contribute to the fun atmosphere of Spider-Man: Homecoming that was so sorely lacking in Amazing Spider-Man, and the world is a better place for it.

Which of these roles do you keep forgetting about? Let us know in the comments!