Not all detective shows are depressing, dimly-lit and shot on a rainy day. Directed by Anthony Migella, The BBC and HBO co-production of “The No. 1 Ladies’ Detective Agency” tells the story of Mma Precious Ramotswe, the first female private detective in Botswana. In addition to being completely clever and observant, this show is a beautifully photographed love letter to Africa. Enjoy.