Sometimes 30 seconds can steal the whole movie.

Here are our most unforgettable movie cameos of modern times.

The uncredited role or cameo has been around as long as cinema has existed.

Other times, it serves to hide the true nature of a role, and sets up a reveal.

Other times still, it provides shorthand for characterization.

And in some cases, its just a funny in-jokeor the actor owed his friend a favor.

yo note: scroll below at your own peril, assome of these are surprise cameos.

Lets get started…

25.

Such was my experience while watchingThe Muppetsand having Jim Parsons appear as human Walter.

The crowd literally cheered and clapped.

Its the perfect merging of a timeless comedy classic with the biggest sitcom of the day.

Watch The Muppets

23.

Having the two theatrical knights return as their iconic X-Men characters certainly did this.

Watch The Wolverine

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22.

But even that brief glimpse is enough to make you wonder at what lurks behind the facade.

Having Portman play this unnamed ghost makes you re-evaluate Jason Schwartzmanns troubled Jack instantly.

Watch The Darjeeling Limited

21.

Its a literal pan across the two mega-stars as they take part as eligible bachelors.

Its Clooney having fun directing and making us have some too.

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20.

Jason Statham Collateral

Of course we had to feature the Stath.

Watch Collateral

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19.

Danny Pudi Captain America: The Winter Soldier

I like to think this really is Abed.

Watch Captain America: The Winter Soldier

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18.

Its sublime, inspired, and utterly ridiculous.

The fact that Bowie plays it all totally serious just adds to the heightened sense of bizarre.

Watch Zoolander

17.

Glenn Close Hook

Speaking of bizarre, this has to be the weirdest entry on the list.

Glenn Close playing a man pirate in Spielbergs not that good, but still beloved, Peter Pan adventure.

Words cant really do it justice, so Ill just let you have a look.

read more: What Went Wrong With Steven Spielbergs Hook?

In an Adventure with Scientists.

Watch Hook

16.

Of course, I knew he was important, but I didnt know why.

Then I grew up, re-watched the film, and got it.

James Bond was only the King of England too!

Watch Robin Hood: Prince of Thieves

15.

Such was Hugh Jackmans cameo as Wolverine in Matthew VaughnsX-Men: First Class.

With the film being a prequel, you were promised an all-new cast of mutants.

Even though Wolverine was around then, you knew he wouldnt run into the X-Men for another few decades.

But how about having young Charles and Erik run into him in a bar while searching for mutants?

Of course, theres only one reaction 60s Wolverine would give them.

Watch X-Men: First Class

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14.

Uttering the immortal line, Dude, can we bring the brewskis?

Watch Mystery Men

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13.

Robert De Niro American Hustle

De Niros best role in years.

As the camera tracks into a grimy casino, youre not quite sure who youre about to meet.

Enter a balding De Niro, with all the weight of past roles behind him.

Watch American Hustle

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12.

But at least they put her in one of the funniest scenes in the film.

Watch Hot Fuzz

11.

Watch Casper

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10.

The sheer absurdity of it just kills me every time.

Being a Star Trek fan, I love the fact that the Slater is one too.

Part of its charm was knowing exactly what to do with its endless celebrity cameos.

Watch This Is The End

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8.

Watch Kingdom of Heaven

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7.

Hes really the only quotable thing in the film.

Watch Wedding Crashers

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6.

Well if youre Lord and Miller, you have him brutally gunned down within moments.

Watch 21 Jump Street

5.

Its vintage Williams, all manic yet focused energy as he spits rapidfire advice.

Watch Dead Again

4.

For years the golden boy of Hollywood, Cruises image was starting to come under sustained fire.

Scientology, odd behavior, and marriage rumors all tarnished his stage-managed wholesome leading man image.

He also hadnt really displayed any of his earlier comedy chops for years.

Watch Tropic Thunder

3.

Samuel L. Jackson Iron Man

The most important uncredited role of recent years?

The reign of Marvel truly started with Samuel L. Jackson popping up and talking about the Avengers Initiative.

Suddenly, anything was possible.

Watch Iron Man

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2.

Alec Baldwin Glengarry Glen Ross

The epitome of all uncredited roles.

Its so good that you forget hes not even in the damn cast proper, and that he hasonescene.

But what a scene.

Proof that the right role, no matter how small, can make your career forever.

Watch Glengarry Glen Ross

1.

Kevin Spacey Seven

Surely the greatest uncredited role in modern movie history?

Extending to this was Spaceys total dedication to his nameless, unknowable serial killer.

Having his name plastered all over the place would have spoiled the mystery.