Given the amount of rumours that fly through the internet, it's difficult to know which ones to give credence to and which are fictitious.

Still, whether they're real or not, it does tell one thing - that the speculation and interest surrounding something is enough to generate it. So it goes with the still-untitled fourth 'Avengers' movie, which picks up directly after 'Infinity War'.

Where last we left Thanos and the plucky Avengers, half of all life disappeared in an instant - balanced by The Snap™ and Thanos returned to his farm, watching the sun rise on a grateful galaxy. Naturally, the speculation is that the second part sees the Avengers trying out some kind of crazy time-travelling in order to reverse the effects of The Snap™ and bringing Captain Marvel, played by Brie Larson, into the mix.

This trailer description, which was first posted on Reddit, seems to catch most of that. What's more, the person who posted claims that they were the ones who leaked the 'Captain America: Civil War' trailer that revealed Spider-Man as a member of the Marvel Cinematic Universe.

Again, you have to take all of this with a pinch of salt - but the reaction both in the subreddit and across other forums is that this description is legitimate and most likely a rough cut of the finished product. The trailer is expected to land online towards the end of November, with an extended 'Captain Marvel' trailer expected around Christmas. Here's the post, in full and unedited.

Final Trailer is about 2ish minutes. But it starts with the 10th year logo, which zooms into the screen in logo fashion but it flashes all colors of the stones as it does

Thanos’ voice: “My Destiny is not yet fulfilled...” A shot of a battered Tony, looks as though he’s still on Titan, confused. “Greater threats arise to undo the balance I lost everything to achieve... and I.... will not... be undone” Shot of Banner and Cap with Vision on a table fades in and out... Shot of Quills ship lifting off. Fades. Tony: “Fury was right.” He’s talking to someone out of view in some type of normal house. This MIGHT be Aunt May, he’s glossy eyed, and the dialogue is spoken over the prior screen, not actually what’s he’s saying. “He was right since day 1...” black screen Tony: scene of him in some sort of garage looking place. In front of 3 different suits, they seem pretty normal? None are the one that was leaked, he has the housing unit in his hands. “I’ll do whatever it takes so that never happens again...” black screen Tony in SHIELD gear. He’s walking towards the camera with soldiers behind him. Shot of Antman standing in the Quantum Realm. Cuts to him surrounded by 3 tardigrades. He’s running, then stops at a green portal type thing. Fades to a shot of Scott in street clothes. Gray shirt jeans and a jean jacket.

Scott: “ I think... I might have a way to help.” Not sure who he’s speaking to. Or if this is even the real dialogue lol. Doesn’t look like it matches.

Shot of an empty throne in Wakanda, various shots of Shuri, M’Baku, and Okoye. Black screen

“This was NOT our fight...” Shuri or Okoye couldn’t tell. Screen still black. Shot of Cap standing arms crossed with Rhodey, Rocket and Thor, in a room that looks like it’s still Wakanda.

Cap: “We need to make this right...”

Banner: “Cap we don’t even know where to start... Thanos is gone. He won.” Thor: “Well... then we had better get to work”

Shot panning down slowly of the pager Fury had in someone’s hands. I’m almost 100% certain it’s in Tony’s hands. A shot of Rhodey suiting up very briefly, from the knees up to the crotch area lol, it’s not nanotech, but looks more or less exactly how Starlords mask materializes with a Thor voiceover: “Are you ready for this?”

Rocket: “Well... if I’m not...” pause. Black Fades in to Rocket, music silences: “What more could I lose?” Bifrost shot w/ Thor, War machine, and Rocket. Various shots. Gauntlet, still damaged, being reached for, shot of Nebula (looks like the same place Tony was earlier) , and then shot of Banner. Black screen. Thor: “We need an army to stand against Thanos...” shot of Thanos putting on armor. “Yours is the only one formidable enough to give us a chance...” shot of Thanos wielding a big double edge sword. “So I ask of you...” Various shots of Black Widow, brief shot of Tony’s suit, Caps new chest piece (chainmail!!!) and banner putting on a purple skintight suit and a button up over it In front of a mirror. Fades to Thor, “Will you help us?” More various shots, including a broken gauntlet on the ground as someone (clearly Thanos) is walking away... same aesthetic and scenery as the one when it’s being reached for. (I think he throws it on the ground??) “It’s been awhile since I’ve been to Earth...” Music is getting louder as it crescendos to a shot of Captain Marvels chest panning up to her face. The scenery behind her almost looks like Xandar. Because it can’t be Earth (that would make no sense) but it’s blue skies and clouds outside a window... Captain Marvel: “Let’s go” Shot of her flying towards something angrily, she cocks back a punch, eyes glowing, flames surround her. She punches, then [Title Card] as Avengers theme plays.

However it doesn’t actually have anything, it’s just a blank screen with the music.. Post theme cutaway stinger, Rocket is in a rolling chair looking at a few computer screens, has on this cool ass white bodysuit.

Rhodey: “I’ve seen a lot of crazy things, but a talking Raccoon? (rocket looks up at him from chair) Definitely tops them all...” Rocket, going from Rhodey back to the computer screens sarcastically: “boy if I had a unit* every time I heard that one” cuts to a shot of Thor smiling with an off queue “Ha Ha Ha”. Trailer ends... This is actually a rough cut. There’s a lot of black screens in the midst of all these lasting 1-2 seconds. This trailer is still slated to debut on Nov. 21,28, or December 12th on Good Morning America. I'm not sure of the scheduling situation. Also, official extended trailer #2 for Captain Marvel will arrive right around Christmas.