Actor Robert Wagner is being labeled a “person of interest” in the drowning death of fellow actor and then-wife Natalie Wood nearly four decades ago.

The Los Angeles County Sheriff’s Department said in an upcoming interview with CBS’ “48 Hours” that after continuing the investigation over the years, Wagner, now 87, has become of interest since he was the last person to see Wood.

“As we’ve investigated the case over the last six years, I think he’s more of a person of interest now,” sheriff’s Lt. John Corina said. “I mean, we know now that he was the last person to be with Natalie before she disappeared.”

Wood was married to Wagner from 1972 to her untimely death in 1981.

The 43-year-old drowned off the coast of Catalina Island, Calif., in November 1981 after she went missing from her family’s yacht. Capt. Dennis Davern and Wagner’s friend, actor Christopher Walken, were also aboard that fateful evening.

Her death was initially ruled an accident, but in 2011 the case was reopened and a death certificate was issued with the cause being “drowning and other undetermined factors.”

“Natalie Wood: Death in Dark Water” will air at 10 p.m. Saturday on CBS, featuring new witnesses, evidence and theories as to what happened the night of her death.

— Nicole Bitette, New York Daily News