Recently, I was with actor Christian Bale and former world-class boxer Dickie Eklund in a crack house on Smith Street in Lowell, Massachusetts.

I should say former crack house. Back in 1993, it mainly served as a safe place for junkies and addicts to hang out and get high. Off and on, for nearly 18 months, I spent time inside the scantly furnished, dimly lit, cockroach infected, two-bedroom apartments on the second floor with a video camera.

In those days, I was a documentary filmmaker. My job was to document the demise of Eklund. He was a crack addict. He’d fought on HBO many times and even went the distance with Sugar Ray Leonard. I put him back on HBO -- but this time as one of three stars in the “America Undercover” documentary film, “High on Crack Street: Lost Lives in Lowell.”

On July 13, Lowell will host the...