Feisty Lisa told him in no uncertain terms that he was in danger of ruining the whole show as it prepares for its big season finale -- when his character, Chandler, marries Monica, played by Courteney Cox Arquette.

And she told him: "You're killing yourself, Matthew, and I for one don't want to be forced to watch you die."

Kudrow, who plays ditzy waitress Phoebe on the hit show, added: "There isn't anyone here who doesn't love you, Matt, and understand that you are dealing with an illness.

"But you must do your part to get better. It's time to get your act together. This is your last chance."

Sources say Kudrow, 37, was the only one who directly confronted Perry as he returned to work on the hit NBC show March 20.

While Friends' bosses hinted that Perry could be dropped for next season, his other co-stars -- Courteney Cox Arquette, David Schwimmer, Matt LeBlanc and Jennifer Aniston -- welcomed him back warmly.

And his onscreen mom, Morgan Fairchild, provided a shoulder for Perry to cry on -- because she remembers him as a 9-year-old who used to visit his father John Perry on the set of Flamingo Road, in which she starred.

"I feel a proprietary interest in him," says Fairchild, 41. "He looks great, lovely," she says.

But Kudrow let him have it, sources say. "Lisa is very fond of Matthew, but feels she and the rest of the cast have been far too sympathetic to his problems. She feels the time has come for them to show him some tough love," says a source.

"Although she is very fond of Matt, she is upset with him and she berated him for causing shooting delays."

As Star reported, Perry, 31, went into rehab Feb. 23, while in Dallas filming the movie Servicing Sarah with Liz Hurley. That film is also in danger because of his prolonged absence and the threat of a strike by actors and writers that promises to cripple Hollywood.

The actor realized his life was spinning out of control through his overuse of the painkiller Vicodin, speed and the heroin substitute methadone -- which doctors prescribe to get addicts off drugs.

This is the second attempt at sobriety for the actor. He spent a stint in rehab in 1997. He was also admitted to an L.A. hospital last year suffering from pancreatitis, a painful condition often brought on by drug abuse.

He detoxed in Marina del Rey's Daniel Freeman Hospital before entering Promises rehab center in Malibu.

Setsiders can only hope that Perry takes Kudrow's tirade to heart. "He knows he has to stay sober, not just for the show, but to stay alive. His doctors have warned him that he's playing with fire. If he continues to abuse drugs, he could lose more than his job. "He could lose his life."