Season 3 follows Abigail Walker, the host of Canada's top morning TV show, who is grappling with the devastating loss of her teenage daughter, Lucy, to suicide. Tormented by grief and regret, Abigail uses the Plan B Agency to embark on a series of time-traveling journeys, desperate to alter the past and prevent Lucy's tragic fate. However, as she attempts to protect Lucy from the toxic relationships that contributed to her downward spiral, the actions create ripples that affect not only Lucy's life but also the lives of those around her.

Abigail's pursuit of a better outcome for Lucy leads her to confront painful truths about her own past, her relationships, and the choices she's made both for her daughter and for herself. She must navigate the complexities of time travel, grappling with the ethical implications of altering the lives of others. But as Abigail travels deeper into the past, she discovers that the true meaning of love and sacrifice may lie in accepting the unchangeable.