Margot and Will cross paths at the local dog rescue centre where - after a series of misunderstandings and a lot of consternation - they agree to foster Blossom (a gentle Staffy with a giant head, soft, floppy ears and kohl-rimmed brown eyes) together: one week on, one week off. Margot and Will don't get off to the best of starts: he thinks Margot is demanding and needy and Just So Much. And she thinks Will is emotionally unavailable, slightly brittle and very mistrustful. They're both right. But the more they bicker, the worse Blossom behaves, and they realise they have to form some sort of truce in order to "co-pawrent" her together. It's almost as if Blossom has plans of her own . . .