Dark Uncle is the third episode of HBO's The Outsider. It premiered on January 19, 2020.
Despite being on mandatory leave, Ralph (Ben Mendelsohn) continues to scrutinize the confounding circumstances surrounding the night of the murder. Frustrated by their lack of progress, Ralph and GBI detective Yunis Sablo (Yul Vázquez) meet with Alec (Jeremy Bobb) and Howie (Bill Camp), who suggest bringing in unorthodox PI Holly Gibney (Cynthia Erivo). Jack (Marc Menchaca) has a hair-raising experience at a remote barn where key evidence and a mysterious substance have been found. Glory (Julianne Nicholson) deals with fallout at her daughters’ school and with Jessa’s (Scarlett Juniper Blum) increasingly concerning nightmares.
A disgruntled Jack Hoskins is sent to join the investigation at the barn where the clothing was discovered. After wasting time, he shows up late to the empty barn, where he is attacked by an unseen apparition. Over the following days, he develops strange welts on his body and his behavior grows increasingly erratic. Ralph goes to Howie Salomon and Alec Pelley with the information he's gathered on the van and the Maitlands' trip to Dayton. They contact eccentric savant investigator Holly Gibney to backtrack Terry's movements during the trip. While attempting to speak with Terry's father at his nursing home, Holly discovers that a male nurse at the institution was convicted of murdering two young girls around the time of the visit. The nurse is shown in prison concurrently, where he commits suicide to avoid being killed by another inmate. Jessa Maitland convinces Glory to let Ralph visit so she can relay a message from the man she's been speaking to at night: Stop, or something bad will happen.