From the very beginning of the investigation into the disappearance of Iris Brown,

everyone suspected one particular person had something to do with it.

She left home with the suspect on the night she was last seen alive.

The suspect's behavior in the days following her disappearance

raised countless red flags and forensic evidence pointed to something bad happening inside

the suspect's car. But proving beyond a reasonable doubt exactly what happened wasn't going to come

quick and easy to the investigators tasked with finding answers.

When this suspect was finally apprehended and charged, it was with the crime prosecutors could prove,

not the crime everyone knew deep down he'd actually committed.

Decades later, a determined detective reopened the case with one mission to give surviving family members a version of closure, even if it meant the killer would never face the consequences.

I'm Kylie Lowe, and this is the case of Iris Brown on Dark Down East.

It was early evening on March 15, 1976, and 27-year-old Iris Brown had just returned home from work to find a friend waiting at the apartment she

shared with a roommate in Burlington, Vermont.

28-year-old Bernard Posey had arrived around 4.30 that afternoon and insisted on waiting for Iris

to get home. He had some good news. No sooner did Iris walk through the door, Bernard announced

that he'd received a message from her boyfriend, Martin,

who was incarcerated at the Federal Correctional Institution in Danbury, Connecticut,

but not for much longer, because Martin was set to be released the next morning.

Bernard himself had been released from FCI Danbury the previous year,

which is where he got to know Martin,

so he offered to drive Iris down to pick him up. Iris agreed to go with Bernard to Connecticut.

It was a nearly 300-mile trip over four and a half hours in the car, so they'd be gone

...