When Ken and Sally Richardson lost their only daughter to cancer, the glue that held their family together dissolved. Wrecked with grief, Ken and Sally are lost and desperate and on the cusp of bankruptcy from their late daughter’s medical bills. But when a mysterious letter arrives, informing the Richardson family they have won a mountain cabin in Montana's luxurious Big Sky region, they’re skeptical of the letter’s legitimacy. When the prize turns out to be real, Ken and Sally arrive in Big Sky in hopes of saving themselves from financial ruin. It doesn’t take long for Ken and Sally to realize the cabin comes with strings attached, and as they follow the threads to the truth of why they were chosen, neither are sure if they’ll survive solving the mystery in Big Sky.