Everyone has done it.
A new big-screen project is revealed to be heading into production, and everything from the director tasked with guiding said feature into existence, some rather underwhelming prior entries in the franchise, or the concept in general just having bad news written all over it, soon leaves you fearing what sort of disaster could be on the horizon.
And many times, a first look, teaser, or full-blown trailer for one of these once-incoming movies quickly reveals that fans were very much right to dread what was being cooked up by certain studios.
But not every time.
That's because every now and again a trailer comes along that reminds you precisely why you should never fully make your mind up on a seemingly doomed upcoming release before you've actually witnessed the animated brilliance, franchise-reinvigorating, or just plain ludicrous action for yourself.
Now admittedly, some of the following outings didn't actually go on to bring home universal acclaim or change the landscape of cinema forever. And a few of the flicks to come haven't even arrived in theatres yet.
But there's still no denying that the first glimpses of each and every one of these movies helped ease the fears of those who initially assumed the picture in question would be an inevitable failure... even if only for a little while.
"Yeah, antman? Serious? I won't watch it. Lame!"
That was just one of the many comments unleashed by some truly baffled corners of the MCU fanbase back when Kevin Feige and the gang announced their second Phase back in 2012 - one that came equipped with the feature debut of Scott Lang's Ant-Man.
Marvel Studios were really opting to throw an ant-sized superhero into the mix before the likes of a Black Panther, Moon Knight, or Doctor Strange?
Yes they were. And from the moment Paul Rudd's thieving eventual Avenger rocked up on screen for the first time during the Phase Two flick's trailer, it quickly became clear why a pint-sized story was the perfect call for the burgeoning MCU.
Blending genuinely hilarious and effortlessly charming humour with some of the most creative action the franchise had produced so far, the barmy concept of Lang commanding an army of ants and transforming a Thomas the Tank Engine set into a chaotic battleground, was the gift just about nobody honestly saw coming.
And sure enough, this small chunk of pitch-perfect footage convinced many a doubter to take a chance on the biggest little guy in the MCU, with the brilliant Ant-Man going on to bring home millions at the box office and earning some particularly strong reviews, too.