Saturday Night Live Jessica Chastain hosts, with musical guest Troye Sivan. 8:29 and 11:29 p.m. NBC
Planet Earth: Blue Planet II This new installment of BBC America’s Emmy-winning “Planet Earth” series premieres simultaneously across several networks. Presented by David Attenborough, the series involved 125 expeditions to 39 countries, with filming on every continent and every ocean. 9 p.m. AMC; BBC America; IFC; Sundance; WE
48 Hours This new episode of the news magazine series examines the life and death of former New England Patriots player Aaron Hernandez, who was found guilty of murder in 2015 and...