The Old Tin Box

Sharon Fox works as secretary to Jack Smart, head of the World Space Agency. A document meant for her boss, lands on her desk and disturbs her deeply. Its contents could have a catastrophic effect on her family.
She takes the document to her cabin at Yellowstone Park and hides it in an old tin box, under the floorboards.
What happens to Sharon?
Will the document ever be found?
What are the consequences for her family?