Marlowe is a very ordinary field mouse who wakes up one morning in a Virginia farm burrow, sticks his head out and decides he is tired of being alone. He collects his precious possessions and sets out across the field for the house and ends up under the old dwelling in the dirt and darkness surrounded by spiders he sees as monsters and other rats and mice.
Marlowe jumps up onto a subfloor and finds a way into the house through a hole in the floor of the kitchen, behind the stove. He leaves his treasure under the house and enters the kitchen where he meets Miss. Penny the house cat and Smoker the Dog - all mouse haters. He narrowly avoids being eaten by Miss. Penny who knocks herself out chasing Marlowe upstairs and under the bedroom door of Cole, an eleven year old.
Marlowe takes refuge in a toy house just his size. He discovers clothes and puts on a doll's suit with a vest, shirt, pants and coat. He also discovers a mirror and takes long looks at himself with his clothes and his new face which includes a huge grin. He finds a soft bed upstairs in the toy house and goes to sleep.
Marlowe is wakened the next morning by Cole and mouse meets man and the real story begins. Cole conceals he has a mouse who wears clothes - Cole thinks he is an alien. Cole and the computer and lots of time teach Marlowe to speak and Marlowe names himself from the letters on a book cover that he copies with a 'miniature golf pencil'.
Eventually Marlowe is introduced to the household of Louise and Lloyd who take weeks to get over the facts which seem like science fiction. During this time Marlowe discovers a treasure left on the farm by Lloyd's father who never divulged its location. The money earned from the treasure allows the poor family to keep their farm and move to new York City where they buy an upscale apartment and live for over a year until the virus comes.
A virus enters California. The virus escapes the cages and confines of medical imprisonment and starts to kill animals at an alarming rate. Cole and his family leave New York in the late of night and by the time they reach their home in Virginia - there is an epidemic.
Lloyd realized early in the epidemic he had to build a wall around the Virginia House, barn and land. When the family arrives back at the compound the world around them had changed forever as masses of people and animals died off from the disease. The compound is protected and self-supporting with solar panels, natural gas and a natural water well. The compound has all it needs to survive until Lloyd comes down with the disease at the same time that a protected center in UCLA in California discovers a vaccine.
At the end of this screenplay, which is Part One, Cole and Marlowe secretly leave the compound on a journey across the country to save his father Lloyd from certain death. They meet Corrie Anne on their first days out who is also seeking the vaccine for her parents. Cole, Corrie Anne and Marlowe go on the most important journey in history and that is the one to save animal life from extinction, not by guns but by a bug you need a microscope to see.