It is 2040 as Annie's marriage to Rob MacKenzie nears their silver anniversary. When Annie becomes ill, Rob decides to comfort her with an unexpected gift. Throughout their marriage, he has secretly assembled a scrapbook filled with headlines, articles, and correspondence with particular meaning to their lives. But when Annie's time on earth ends sooner than expected, Rob is left to reflect alone on the love, laughter, and events that surrounded their life together.

In 2015, Annie and Rob intertwine their lives in marriage while trying to save an environment under duress. As a Colorado attorney, she battles fracking companies while acknowledging the futility of warehousing nuclear waste. When she confronts an inept city council unable to formulate a plan to assist the homeless, she wonders if they even care. Meanwhile, Rob teaches at the University of Colorado. He challenges fledgling scientists to think clearly and write concisely while alerting his students that the environment is unraveling. Creating a peaceful home life, displaying purposeful public lives, and pushing forward to help the less fortunate, will they be able to prevent Earth from descending into a dystopian spiral?

Sundown Requiem shares poignant moments, current events, and correspondence that surround a twenty-five-year marriage as lovingly chronicled in a scrapbook.