Don't worry there are no spoilers here and secondly these are official prequel stories that can be termed as "canon" for Batman v Superman Dawn of Justice and for the DC Extended Universe at large. These comics books explains the events that took place between Man of Steel and Batman v Superman Dawn of Justice from a timeline perspective.
American soft drink company Dr. Pepper and food company General Mills made a deal with Warner Bros. Pictures wherein they can sell Batman v Superman branded products and in return those products comes with prequel comics that ties with the stories of Man of Steel and Batman v Superman. Enough with these details let's get into actual stuff starting with..........................
CHAPTER 1 - BATMAN (DR. PEPPER)
1) Firefly Exists in DC Extended Universe
DC fans would recognize this bad guy from Batman's rogue gallery, a mercenary who has a knack for fire and explosives based weaponry and specializes in sabotage missions and it's been revealed that he's a reputed saboteur with high standards and perfectionist complex in this movie universe.
2) Batman Has Become Darker And Violent Over The Years
As Ben Affleck said, Batman/Bruce Wayne is undergoing an existential crisis post Black Zero Event (Zod's invasion during Man of Steel) and we can see that it affects The Dark Knight very personally and psychologically.
3) Lex Luthor Is Keeping Tabs on Batman And His Activities
It's interesting to know that Lex Luthor has installed spy cams across Gotham to monitor Batman and his activities, we don't know his intentions for now (something which we will learn while watching the movie come March 25th) but when a super manipulative person is onto to you, things could get worse for sure.
CHAPTER 2 - LOIS LANE (DR. PEPPER)
1) Lois Lane Is No Damsel In Distress
This woman is a perfect combination of brains, beauty and brawns, she was after a millionaire businessman telling him that she's going to expose his illegal activities right to his face and when he pulls out a gun, she uses her situational cleverness and KO's this guy!
2) Kryptonian Technologies Are Illegally Sold In Black Market
The Kryptonian technologies from the wreckage on ground zero (during Black Zero destruction) are illegally acquired and sold on black market, and it's a very serious issue as we know the immense capabilities of Kryptonian tech, one can only hope that it doesn't fall on the wrong hands.
CHAPTER 3 - SENATOR FINCH (DR. PEPPER)
1) A Sub-Committee Created A CG Simulation To Analyze The Potential Destruction Capability That Superman possesses.
The figures are like this.......
- Death toll in five figures within 8 minutes of attack
- Military response being completely useless, no matter how swift they were
- Restriction to deploy heavy weapons, as it leads to more property damage and death toll
- Entire city and half of it's population destroyed under half an hour
2) The Politicians Are Both For And Against Superman
This sub committee is debating on how to proceed with the Superman issue and the kind of problems that might arise due to his existence or what would happen if he ever goes out of control or decides to clean up the world under his own ideals.
But it's safe to say they are on neutral ground because they are both in support of Superman but also fearing him, given his god like powers and mysterious nature.
3) Senator Finch Is On Neutral Ground But She Sees The Bigger Picture
Sen. Finch isn't against Superman, she's a realist and sees the bigger picture because the only problem faced by them is "We don't know about this Superman and we need to know about him to proceed further"
Thus she wants to study Superman and know everything about him, to take a fully informed federal level decision on the Superman issue.
NOTE: They have already started their studies and calculations on Superman for some time and it's going to become more aggressive.
CHAPTER 4 - SUPERMAN (DR. PEPPER)
1) Superman Is Doing "Heroic Acts" (But Within USA)
Throughout these prequel comics, it has been heavily emphasized that Superman was doing what he always does in the comics, saving the people and the world which ranges from putting out forest fires, saving people from a malfunctioning train to street level crimes and much more.
2) The Media Is Debating About The Superman Issue As Well
It's clear that the world is split 50-50 on the Superman issue post the events of Man of Steel and it's really interesting to see the social and political commentary on Superman's existence and what it means to the rest of the world, makes it more grounded and real.
As the teaser trailer says "Is it really surprising that the most powerful man in the world......should be a figure of controversy"
3) Lex Luthor Is Keeping Tabs on Superman As Well
Lex Luthor is clearly scheming something big
CHAPTER 5 - LEX LUTHOR (DR. PEPPER)
1) Lex And His Public Facade
As we have seen from the trailer #2 of this movie, this one shot comic book fleshes out that facade even more and shows the public face of Lex Luthor in a better light.
2) Thomas Kord (Blue Beetle) Receives Easter Eggs, Right, Left And Center.
A billionaire businessman who is also a crime fighter and employs hi-tech equipment to fight crime and in the cinematic universe he's also a playboy, interestingly this character received the highest amount of easter eggs and we haven't even seen the movie yet!
It's safe to say we would see a live action Blue Beetle when Justice League 1 comes around by winter 2017.
3) Superman Never Involves Himself In Political Issues
Superman is quite clever, he never intervened in any delicate political issues till now, he's not flying into restricted air space and he's not interrupting a war so on and so forth.
The American government hopes he never intervenes and the media is debating whether it's good or bad for Superman to intervene in a political issue considering he can solve it pretty easily and Lex Luthor just makes fun of it saying he's going for the easy and convenient route.
4) Lex Luthor Is Obsessed With Superman
This is a no brainer, Lex hates Superman passionately to an extent it's unconditional and that drives him to know everything about Superman so that he can take him down no matter what.
These 5 chapters are from Dr. Pepper tie ins and there are 4 more comics to come from General Mill's Batman vs Superman cereals, one tie in has been released already, I am waiting for the other tie ins to release, post which I'll write the "Part 2" of this article.