Our story would have 3 main characters: a Father and his Son (read equivalently as Mother / Daughter, no sexism intended) and the father’s best Friend during their teen years. The Father is born around 1953 so as a young teen he experiences first hand the birth of prog.

Assuming that a double album has a structure of “4 sides” as in the old vinyl double albums, the storyboard could be something like below.

The music should be original (not simply clone fragments of the different prog styles in history) but at each point in the story it should somehow cleverly integrate distinctive elements which would evoque the era being represented.

1st Half of Side 1: The Birth of Prog.

Our main characters Father and Friend enjoy their early teens as best mates, following up closely the morphing of pop and jazz into prog, of which they become huge fans. The music recreates this period, integrating some psychedelic and proto-prog elements, gradually becoming more perfected and complex.

2nd Half of Side 1 + 1st Half of Side 2:  The Rise and Peak of Prog

The Father and his Friend grow up immersed in the prog atmosphere of the early 70’s, the feeling is euphoric and they decide to form together a business distributing and selling prog records and promoting tours and gigs of prog bands. They have great success and make good money, but at the same time they are taking some risks with significant investments.

The music obviously recreates the golden years of complex and bombastic prog, with elements reminiscent of Genesis, Yes, ELP, VDGG, GG etc.

2^nd Half of Side 2:  The Fall

At this stage of the story (mid 70’s), the Friend is approached by some mass media magnates without scruples who tempt him to switch to the easy money of commercial pop. The Friend finally succumbs to the temptation and betrays his best friend (our Father), taking all the money from their business and escaping to work as producer for cheap punk, pop and disco “stars for one day” (every story needs a bad guy, right?  ). Our Father is left in bankrupcy and total misery (just as some of our beloved bands), but he still follows up faithfully the last flutters of prog (the “pop-tized” prog of the late 70’s).

The music here would include some references to the pop-punk-disco and the AOR-tized prog, but would convey a dark, sad, dying feeling. 

Side 3:  The Underground Survival (from the 80’s until now)

Our Father is poor in extreme after all the debts left by his traitor Friend, but he tries to survive with a hopeful and positive mentality, he gets married and around 1995 he has his Son (who will eventually become our hero and savior of prog).

During these years prog does quite the same, trying to survive in difficult times thanks to a faithful and hopeful underground bunch of followers. It’s the years of Neo, the birth of Prog-Metal and the more diverse variations of the 00’s decade prog, and the music obviously recollects elements evoquing all of these.

The Father puts his Son from very young to study music, providing him with classical training and he also teaches him all the good prog which has been his passion for all his life. As it happens, the boy turns out to be a musical genius, a wonderboy (a sort of modern Mozart), and soon masters the secrets of good music and learns to play a large array of instruments. Under the guidance of his Father he discovers all the good prog of the past and present and becomes himself a fan. And as with many kids of our times, he happens to be also very skillful with computers, a young brilliant hacker…

Side 4:  The Rebellion and the Resurrection

Our Son is a young man and starts to write the most beautiful music humans have even produced. It has the best of all worlds, the delicacy and richness of the best classical music, the energy of the best rock, the sophistication of the best eclectic and avant… it’s a new kind of prog, the music for the future, but the music business world and its factual powers are not happy with it, they turn him down everytime he tries to disclose his music, they are scared of losing the fountain of easy money which the 21^st century pop-dance music has become. Our Son suffers a shameless boycott.

Undefeated, our Son uses his hacker skills to infect every computer on Earth with a very special virus: everytime the user tries to use his computer, the machine will show him one of several things: some of the best songs or fragments of prog history, some message evidencing how manipulated the public is by the mass media oligarchs (of which the Friend has become one of them, of course), and also some of his new beautiful music which is being banned by those oligarchs without scruples.

The human society finally realises that they are being manipulated and rebels against the mass media, on a worldwide scale thanks to the power of the internet. The new prog music flourishes again and reaches everybody’s soul, our Son becomes a hero and the most praised musician on Earth. It’s a new Renaissance, a new Enlightenment era, not only for music but for all of human culture.

Now, this last 4^th side is about a prog era which does not exist yet, so the music would have to be innovative and brilliant, just as the story suggests...