Clint Eastwood is set to appear in conservationist filmmaker Katie Cleary’s new wildlife documentary "Why On Earth," and she recently shared how he ended up on the project and what it was like working with him. The new documentary will focus on nature, wild animals and the relationship between humans, animals and plant life. "We're showing what's happening to elephants, rhinos in Africa, the palm oil epidemic in Indonesia and Borneo and Sumatra, and how it's affecting the orangutans," Cleary told Fox New Digital.