'Longmire' season 5 spoilers, plot news: New trailer hints on an amnesiac Walt; Henry's lies get exposed

"Dishonesty is disloyalty."

This is what Sheriff Walt Longmire (Robert Taylor) tells his Cheyenne friend, Henry Standing Bear (Lou Diamond Phillips) in the official "Longmire" season 5 trailer released by Netflix.

According to the official synopsis of the hit crime drama's fifth run, Henry finds himself right in the middle of two opposing parties, where his loyalty to one could mean his death to the other. Fans have been speculating for months that Walt and Henry will find themselves at odds with each other in "Longmire" season 5. Now, it looks like the rumors have just found a basis in the upcoming installment's truths.

In an interview with Access Hollywood Live, Phillips shared that Walt and Henry's friendship may indeed end soon, due to Henry's secret life as a vigilante, taking up the role of Hector after the real Hector (Jeffrey De Serrano) died.

The trailer released for the upcoming season also shows that the series will be picking up where it left off. "Longmire" season 4 ended in a cliffhanger finally where Walt and his girlfriend, Dr. Donna Sue Monaghan (Ally Walker), were shot at by an anonymous armed intruder while the two of them were caught in an intimate moment. The bullet hits Walt, who is shown in one scene looking lost and saying that he does not remember anything. This unfortunate amnesia comes at a bad time since it's now been made clear that the long-time sheriff of Absaroka County is being hunted.

Other upcoming complications include Cady Longmire's (Cassidy Freeman) deal with the local businessman, Jacob Nighthorse (A. Martinez). The official synopsis describes this deal as "the ultimate betrayal for her father." Meanwhile, Walt's deputy, Victoria "Vic" Moretti (Katee Sackhoff) gets caught in a romance steeped in deception with fellow deputy Jim "The Ferg" Ferguson (Adam Bartley).

"Longmire" season 5 kicks off on Friday, Sept. 23. Seasons 1 to 4 are available for streaming on Netflix.