Book Riot s Mystery Deals of the Day for October 4 2021 - 61Book Riot s Mystery Deals of the Day for October 4 2021 - 63Book Riot s Mystery Deals of the Day for October 4 2021 - 55Book Riot s Mystery Deals of the Day for October 4 2021 - 2Book Riot s Mystery Deals of the Day for October 4 2021 - 79