Longmire Season 4 Plot and premiere update: Walter to investigate Cady's mother's murder mystery?
Longmire season 4 will premiere on Netflix this summerLongmire/Facebook

The filming of Longmire season 4 will finally begin this month but Netflix is yet to announce a premiere date.

The writers of the series have teased that the upcoming season will be the best with a lot of history being played out.

This has given life to already existing rumours that Walter Longmire will investigate his wife's brutal murder. As of now characters in the series including Cady, think she died of cancer.

Walter may reveal his painful past to his daughter after Cady confronts the sheriff when she learns some facts related to her mother's death.

Walt will be investigating episodic crime stories in the upcoming season and the real reason behind his wife's death will be a continuing storyline when the show returns on Netflix.

Tony Tost, who enjoys teasing fans with his writer's room tweets, has said that the series will go on production in late March.

The news was later confirmed by actor Lou Diamond Phillips who said that filming for the next season will begin in two weeks.

A&E's hit crime drama was cancelled in August last year after a successful season 3, much to the disappointment and shock of the show's cast and crew along with their loyal fans.

Phillips has been vocal on social media since the popular drama was abruptly cancelled and had appealed to fans for support before the series was picked up by Netflix in November.

Season 4 is expected to premiere during summer this year with Robert Taylor and Lou Diamond Phillips all set to reprise their roles of Walter and Henry respectively.