The series involves Mark and Maeve, who did not previously know each other, dying on the same day in separate incidents, then finding themselves continuing to exist as ghosts, or shades.
Mark and Maeve help a long-married elderly couple who are facing death find redemption by exploring the meaning of honesty and forgiveness in their relationship.
A young nanny learns to accept responsibility for the unintended outcome of a relationship with her married employer.
Throughout, Mark agonizes over being able to approach the children he left behind, while being unable to truly bridge the gap between life and death.
Finally, the unexpected ending touches on the need to accept the changes life thrusts upon us and let go in order to allow ourselves — and our loved ones — to move forward.