In the same vein of tree planters and lighthouse keepers, Mary Kelly flips the over-romanticized lifestyle of fire observers made popular by Jack Kerouac and shows us how lonely freedom really is. When Mary meets Daniel, a handsome quirky potter, sarod-player, and fire lookout observer, she falls in with a tribe of young people who earn a living by watching for smoke and fire in the mountain foothills of Alberta. For several summers, Mary commutes each weekend from Calgary to Daniel's isolated post on Mockingbird Hill, where she gets a close-up look at the job in the clouds. Dissatisfied with her own job in a health food store selling vitamins and herbal remedies, she and Daniel concoct a plan to leave the city and move to the woods of interior British Columbia. On a remote acreage above Shuswap Lake, they erect a yurt, and dream up ways to earn a living without joining the local pot growers. Debt and unemployment ensue.

Disillusioned with the limited employment options in a rural community, Daniel rejects the pressure to sell his art work, and decides to go back to fire lookouts. In spring of 1992, Daniel is posted to Moose Mountain Lookout west of Calgary, a rocky summit at 8,000 feet. Unemployed, Mary follows him back to Calgary to resume their weekend visiting schedule and hunt for work. But that summer a series of betrayals and violence explode apart relationships and friendships, transforming the group of lookout friends.

On Mockingbird Hill is an account of the idealized lookout lifestyle made popular by Jack Kerouac. It is also a story of couple's search for meaningful work. Kelly's reflections look humorously on gender, and how sometimes, our lives mysteriously and briefly intersect with others, leaving an imprint and forcing us to look inward.