The shocking Tom Cruise-Sumner Redstone feud escalated into a full-blown War of the Words Wednesday, with Cruise's camp slapping back at the media mogul, saying he's the one who has lost his mind.

Bert Fields, the powerful Hollywood lawyer who represents Cruise, told The Post that 83-year-old Redstone "was a mighty mogul once who has self-destructed in front of everyone."

Those fiery comments came a day after Redstone, who controls Paramount Pictures' parent company Viacom, publicly bashed Cruise for the actor's bizarre off-screen behavior. Redstone said Cruise's personal conduct "has not been acceptable" to the studio.

Click Here for the Tom Cruise Celebrity Center

Fields defended Cruise's oddball behavior — and said the real losers are the shareholders in Viacom.

"What was his personal conduct?" Fields asked. "Jumping on a couch on Oprah Winfrey because he's in love with Katie Holmes? That really deserves the death penalty?"

"Or speaking out against mood-altering drugs for children? That's a real reason for the shareholders to be deprived of billions of dollars?"

Over his career, Cruise's movies have raked in close to $3 billion in ticket sales in the United States alone.

All of Hollywood was picking its jaw off the floor Wednesday after the bitter parting of ways between the star and his longtime studio home — but no one's jaw dropped farther and faster than Paramount boss Brad Grey's.

"Redstone decided to make this announcement totally independent" of Grey, said one source close to the matter.

This source said the studio boss was "caught off-guard" by Redstone's comments, made Tuesday to a Wall Street Journal reporter before boarding a plane to Aspen to give a speech.

Paramount was in chaos Wednesday, as executives worried that Redstone's remarks would drive away other movie stars from the studio.

"People in the company are upset about this because it makes Paramount seem like a less talent-friendly place," said a source.

Paramount and Viacom had no further comment Wednesday. Both Grey and his boss, Viacom CEO Tom Freston, planned to make the announcement in a more graceful way, said a source.

Even if the principals weren't speaking on the record Wednesday, plenty of people in their orbits were.

Redstone's comments, which severed a lucrative 14-year relationship between Cruise and Paramount, rattled many Hollywood executives, who said they could not recall an executive so publicly dressing down such a megawatt star.

"I think it's reprehensible," said one high-level executive at a rival studio, calling Redstone an "old fart."

"Tom Cruise hadn't hurt anybody but himself," this person said, "and he can make a comeback. We'll all be in business with him if he comes with the right script."

A source close to Redstone fired back, saying, "He's blunt. He says what he thinks. Maybe in Hollywood that's a rarity."

The Cruise camp, already under siege for the actor's increasingly weird behavior over the last year — everything from going bonkers on Oprah's couch to ranting to NBC's Matt Lauer about antidepressant medication — quickly responded to Redstone Tuesday evening.

Paula Wagner, Cruise's partner in the film company Cruise/Wagner Productions, called the remarks "offensive" and "undignified."

"Whatever remarks Mr. Redstone would make about Tom Cruise personally or as an actor have no bearing on what this business issue is," Wagner said. "There must be another agenda that the studio has in mind to take one of their greatest assets and malign him this way."

A source close to Redstone insisted Wednesday that the issue had nothing to do with money.

Reports claimed Paramount would have kept Cruise on the lot had he lowered his price, said to be close to $10 million annually plus a hefty cut of the box office.

Click Here for the Tom Cruise Celebrity Center

For more news, entertainment and sports coverage, click here for NYPost.com.