Vida lives in Riding, a village in the middle of a dark and dangerous forest where no one dares venture outside the walls protecting them and their houses. She dreads the day her grandmother will turn sixty-five and her Retirement will happen. She wishes with all her heart that Grandma Oda would be granted the right to live longer, but in her town, the Wolves come to take away the elderly who can no longer contribute to society. In her town, Retirement means death.

After her grandmother has been taken away by the Wolves, Vida goes to her house to say goodbye one last time to the things she once knew. But when going through the possessions Grandma Oda left behind, she discovers a note addressed to her - a note from the mysterious Crimson Guard.

'Your grandmother is not gone. And she needs you.'

Will Vida be brave enough to look beyond the walls that keep her safe - and locked up?