Matthew Perry went to rehab scores of times but it never stuck, and a new TMZ documentary explores how some of these facilities can do addicts way more harm than good.

TMZ Studios has a new documentary — “TMZ Investigates Matthew Perry and the Secret Celebrity Drug Ring” — which airs on FOX Monday night at 9 PM ET and drops Tuesday on Hulu.

The documentary exposes how a ring of doctors, enablers and rehab centers fuel the addiction of celebs, who pay them all a fortune for services that are the opposite of helpful.

Kelly Osbourne, a recovering addict herself, talks about body brokers — people who work with certain rehab centers and stand outside AA meetings, looking for addicts who appear to be struggling. The body brokers get the addicts re-addicted and then guide them to the rehab center, which cashes in big time.

It’s a shocking look at the doctors, enablers and rehab centers that have caused enormous grief and, as in Matthew Perry’s case, set the table for fatal encounters with drugs.