^^^ That is a cool premise Jax but I think HBO or Showtime would be a better venue for that type of show. ABC is owned by Disney and that seems a little dark for Disney.
It probably would suit cable better but how many cable shows reach 100 episodes though I guess the concept could be lowered in episodes but 100 days sounds cooler

. The whole event would be and forgive me because my science is rusty...
* 2012 the Hyrdon Colliader, which after years of issue has been running at peak power for many months now goes off the chart and for several seconds creates hundreds of miniature black holes all over the planet, so small though they evaporate within seconds. They cause some short term damage in terms of weird climate but things settle down and everything is hushed up. However several weeks later its found the Earth's core is actually slowing down weaking our magnetic field and causing other side problems like earth quakes which will only get worse. The reason for the problem is one of the black holes appeared in the core and didn't evaporate feeding off the geothermal energy to sustain itself. Its so small it would take a long time to actually grow in size and swallow the earth but long before that in 100 days the magnetic field will fail and there is nothing we can do.
Like I said science is rusty but hey its TV who cares
Season 1 would be the news leaking but the true cause of the problem kept hidden, while governments try to fix the issue and silence anyone who tries to tell the world the true reason behind the crisis. I would keep the black hole bit though for the final scene in season 1 and before that the viewer would know only about the issue with the core/magnetic field but not know why. Pick different groups of people to focus, showing flashbacks like LOST for backstory. Society pretty much falls to pieces as the effects become more real and people begin to believe the end is coming.
The whole multi verse thing would be a penulinate season plot which started at the end of the previous season so season 3 into 4 going off the original concept. This would get weird SCI FI in a episode called "The Bleeding Effect". The Hydron Colliader proved the exsistance of the multi verse theory but what is happening to our world is bleeding into another Earth and then will happen to another and another. Earth 2.0 has similar though slightly changed history and there Colliader while peak power has not triggered the effect and this season would focus on several characters on Earth 2.0 trying to stop the event befalling this Earth and find a way to stop the bleeding effect that even with the colliader turned off will cause the same issues even if a Earth history never built the device. Side effects of being on another Earth is its slowly killing our Earth characters meaning its not a way out to survive our Earth's fate.
That season is probably the hardest to make sense off but I just like the idea of the multi verse and its also a chance to see what our characters lives might of been and makes it harder on our characters seeing what might of been for them and Earth if there fate was not already sealed.
Final season would be basically last days and of course one last ditch attempt to save Earth though it would fail. Peple would have to choose do they want to live to the end or commit suicide first a major character cull in last season.
anyway just a idea I had when on the loo

seriously I think of random shit when on the loo.