Blue Planet UK Main cast, played by Steve Brown Episode 1x01: Episode 1 (Mar 25, 2019) Episode 1x02: Episode 2 (Mar 26, 2019) Episode 1x03: Episode 3 (Mar 27, 2019) Episode 1x04: Episode 4 (Mar 28, 2019) Episode 1x05: Episode 5 (Mar 29, 2019)