David E. Kelley -- creator of some of TV's most popular up-to-the-moment dramas such as Ally McBeal -- is going to war against ABC.

The modish producer -- and husband of movie star Michelle Pfeiffer -- is in a rage over ABC's disastrous decision to move his most popular show, The Practice, to a new night.

This week the network moved the long-running legal drama from Sunday night -- where it had played to great ratings for nearly four years -- to Monday, where it suffered its worst ratings in memory.

A fuming Kelley told the Los Angeles Times the move was "an act of stunning stupidity, which did all the damage it was meant to do."

"The Practice" was crushed in the ratings by Joe Millionaire, the new Fox reality hit, and ended up in fourth place.

On Sundays, The Practice was usually the top-rated show.

Kelley said that if the show returns next season -- its current license is up at the end of the season -- it won't be on ABC.

His threat appeared to have been made in anger, because he doesn't have control over that decision. Even Kelley says he doesn't know why the network would jeopardize one of its prize shows.

"When you try to guess what's going on inside their [ABC exec's] minds, it's dark and it's cavernous in there," he said bitterly.

Kelley and officials at the show's studio, 20th Century Fox Television, had lobbied against the move, sources say.

ABC officials have denied the move was intended to hurt the show.

"I understand emotions are running high right now, but it would be totally contrary to our interests to intentionally damage a show and our schedule," ABC Entertainment Television Group Chairman Lloyd Braun was quoted as saying.

In place of The Practice, ABC is airing a revival of the classic cop show, Dragnet, starting Sunday night

ABC reportedly pays about $6 million an episode for The Practice.

Kelley's threats to take the show to another network after this season may ultimately prove hollow.

"ABC has the option to match any offers from rival networks," a studio source said.

Moving The Practice is something of a slap in the face for Kelley, who once seemed to be on his way to taking over prime time -- but now looks down on his luck.

It was just four years ago that Kelley pulled off a stunning coup by winning the Emmys for both the best drama (The Practice) and best comedy (Ally McBeal) in the same season. No producer has ever accomplished that before.

Now, he's lost three prime-time shows in the last three seasons.

Last year Fox canceled Allyã and then yanked Kelley's replacement show, a lightweight detective series called girls club after less than a month on the air.

In 1999, Kelley tried to launch another new girls' detective show, Snoops, on ABC -- but that too only lasted a few weeks.