The General Synopsis

Preliminary plot line

Part I: How It All Began - Leading to the Catastrophe (prequel that sets the stage, not the catastrophe itself)
Part II: The HAARP Project and Implants
Part III: Breaching Security – A Contained Incident
Part IV: Breaching Security – The Birth of the Undead
Part V: Meanwhile in Portland – Virus SD1 Outbreak
Part VI: The Outbreak – The first Epidemic of Virus SDR1
Part VII: The Rise of the Zombies – Global Infection
Part VIII: Finding the Truth - Seeking what really happened
Part IX: Seeking - Fighting Back
Part X: New Mission - Protecting the Week & Seeking a Cure
Part XI: Finding a New Refuge
Part XII: Survivors of the Long Famine
Part XIII: Winning Over the Evil – A Final Battle
Part XIV: A New Beginning for Mankind – The Golden Age
Part XV: A Broken Hope

Some parts may be changed, extended, split or merged. It's just a brainstormed idea starter.