Al is lonely. Not a temporary or recent loneliness, a long slog of loneliness. Al isn't actually alone however. A therapist-cum-confidant-cum-philosopher called Mouse is Al's only ally. Mouse is just that... a mouse. More accurately a mouse anthropomorphised inside Al's head. Al has come to rely on the guidance and comfort that Mouse provides but as Al's world starts to expand there's less and less room for Mouse...