Lost for centuries, an ancient cup possessing divine grace was hidden away to protect it from a shadowy power known as the organization.

The silence breaks in the winter of 1961 when Mark’s best friend—a Jack Russell Terrier named Mrs. Henry—takes a sip from a stranger's battered cup during a day out on the ice. The ancient relic awakens, granting the scrappy dog divine agency to manifest the impossible and pull the strings of fate.

With the organization's relentless agents suddenly hot on their trail, Mrs. Henry and Mark hit the highway. Along the way, they pull a scruffy musician named Bob from his complacent life in Dinkytown, embarking on a high-stakes, cross-country trek to New York. As the trio desperately dodges their hunters, Mrs. Henry warps the very fabric of their journey. She summons inexplicable intersections with the musical giants of the day, conjuring the exact catalysts Bob needs to find a voice that will define generations.

In a world of secrets and shadows, a boy, a musician, and one remarkable dog are all that stand between an ancient power and the corruption of mankind.