Hi, Dateline listeners, it's Josh Mancowicz, and I'm here to tell you about a very special documentary series premiering this weekend on MSNBC.

It's called The Sing Sing Chronicles, and it follows my Dateline colleague, producer Dan Slepian, and his 20-year journey, investigating five different homicide cases in New York City.

Dan was on a quest to determine whether the men

convicted in those cases were actually guilty. The series is built on more than a thousand hours

of videos he himself shot, and what Dan uncovered will surprise you. So don't miss this special

two-night television event airing Saturday and Sunday, November 23rd and 24th

at 9 p.m. Eastern Time on MSNBC. Now here's an exclusive preview from the Sing Sing

Chronicles. It was right after 9-11.

The NYPD were the heroes of the city, the rock stars of the country.

And I thought, maybe I can have access to the NYPD to follow these detectives as they investigate homicides.

I was embedded with Bronx homicide detectives. Let's come down and open the door.

Bobby Adelarado.

And his partner, John Schwartz.

So you've been a cop a long time.

Almost 20 years.

This is the twilight of your career.

I walked into that building so young, eager, so unbelievably naive.

These were tough guys and I was ready, you know,

to see how they solved murders.

That's why I was there.

We were out at dinner one night and I said to Bobby,

you must bring this job home with you, everything that you see.

...