When does Nexo Knights return?

Nexo Knights (stylized in all caps) is a 3D-animated television series that aired on Cartoon Network and premiered in 2015. It was produced by the Lego Group to coincide with the Lego theme of the same name. The series is based on a highly-futuristic fantasy concept, blending medieval themes with futuristic inventions such as holograms, lasers, and mechs. Four seasons were produced, for a total of 40 episodes. The fourth season finished airing in 2017. A fifth season was intended to be released with 1 wave of sets releasing for it; however, the show was cancelled before it aired.