Should an episodic adventure PC game release a shorter (very shorter) "PROLOGUE" episode for free? Thread

Hello, quite simple question- we are planning a "serious-drama-thriller" like (NO cartoon or stylized) "2.5D" point and click adventure game (not fully 3D, only characters and few other things in 3D, backgrounds pre-rendered). With "episodic" (rather chapter like) format 4-5 "episodes". Each "episode" (we will call them chapters or something) probably 6-8 hours of gameplaye, price probably 19,99 USD per chapter/episode. Time frame between "Chapter" releases should be probably 3-6 months (rather closer to the 6 months).

Production values quite high (full motion capture, nice realistic graphics/backgrounds, Nice realistic characters and faces, probably also facial capture; we have some experience individually, this wont be our first game)etc. It tackles some quite well known (like world known) issue/theme (so i believe its something like using some NOT well known franchise name).

My questions:
1) Is it a good idea to, besides making 4-5 regular "chapters", each around 7 hours of gameplay- released one each 6 months. Besides this, do you believe it is a good idea to release also shorter (around ONLY 1 hour (vs 7 hours)) PROLOGUE "special chapter" for FREE? As a "demo" or rather for promotion reasons? The "Prologue" would be released of course along with the 1st (regular) chapter of the game (so anyone who played the prologue for free and liked it, could imidiatelly buy the 1st chapter).
2) Im not sure if the prologue should contain the actual beggining of the story, or some prequel stuff, or (and i like this the most) would contain a rather "side story" (that is happening at the same time of main story of 1st chapter, but is only mentioned in the regular 1st chapter).

What do you think about this? Would this help to "advertise the game", whats your experience, what did you heart on this account?
(I know only about two similiar games who attempted something similiar but im not sure how it worked out for them in the end... (the games: The Lion's Song: Episode 1 - Silence and The Descendant: Episode 1).

Whats your take on making special shorter additional "zero" chapter released for free (for promotion reasons) in story driven "episodic" adventure point and click game?

A prologue in my opinion should be something that introduces something about the world, the characters - hero or villain - or an event that is a precursor to the main action of the story. A believe the book of Game of Thrones starts off in this way. I don't remember much of it but I think it involves some of the Night's Watch being attack by the Others and one of the character's escaping who is later executed by Ned Stark for desertion (looked most of that up on Wikipedia). It's a good way of getting a bit of action in, posing a few questions and then settling in for a longer story.

Well if you will charge 19.99 per episode , give one full lenght for free like Telltale did with Walking Dead etc ,

Always releasing a playable demo is a good marketing move, if of course, you believe in your project strong enough to know that people will still want to buy your product after playing the demo.

About your second question. Everything depends on how much important info is shown at the beginning of the game. Is there any twist you prefer to save, or is there something special that will make your game stand out from the rest.
Sometimes its good move to show little at the start and gradually show more and more as the game progress. Most games today show best parts of the project at the start of the game or trailer leaving people disappointed that the rest of the game does not grow but rather goes downhill after the start.

So, if you believe in your project. If you really know what you need to show to keep people interested and still leave a lot of it after the demo than yes, its a very good move to release free demo. (One of the games that already done that in a very good way is System Shock 2 created currently on Unreal Engine 4).