Robert Wagner remains a ”person of interest” in the 1981 death of wife Natalie Wood because the LA County Sheriff’s Department says the details the 87-year-old actor gave about what happened ”really don’t add up to what we’ve found.”

Homicide Lt. John Corina says Wagner’s a person of interest as he was the last one with the 43-year-old Wood before she went in the water.

”We want to know what happened from the time of the argument to when she got into the water.”

Wood drowned in November 1981 while boating off Catalina Island in Southern California with Wagner and friend Christopher Walken.

Wagner has said he became jealous and argued with both of them and that he was unable to find her later, searched the boat along with the captain and noticed the dinghy was missing.

Wagner said he assumed is wife had gone ashore.

In 2012, the LA County coroner’s office changed the cause of death from ”accidental drowning” to  ”drowning and other undetermined factors”.  

Officials cited bruises on her body as the reason.

Last week authorities said Wood’s death was now being treated as ”suspicious” after new witnesses had come forward.

Wagner has so far refused to speak with investigators since the case was reopened in 2011.