On a chilly February morning, a battalion of 700 corrections officials led by new Warden Ronald Hutchinson stormed into the Maryland House of Correction in Jessup. Their target: convicted murderer Dennis D. Wise, a godfather-like inmate who oversaw a well-organized and lucrative contraband empire from within. Corrections officials had long since concluded that Wise ran the prison. Nothing short of an invasion could restore order.

Operation Ninety-Nine, as it was dubbed, went as planned. Wise was relocated to Arizona, his network of inmate deputies transferred to a maximum-security prison in Baltimore. But in the aftermath, a new problem has emerged: prison gangs fighting to fill the power vacuum Wise left.

Just weeks ago, Hutchinson's men found that one gang was using cellular phones in prison to conduct drug business on the outside. A black Muslim gang appears to be in the process of consolidating power, which concerns prison officials. Unannounced raids and prison espionage are becoming part of daily life at the largest maximum-security prison in Maryland, where Hutchinson labors to control more than 1,100 of the state's most dangerous criminals.

"It's always a battle. When we take one group out, another starts to rise," said Hutchinson, a stocky, gregarious man with a playful sense of humor. "The best we can do is to hit gangs before they become too active."

Hutchinson, 51, has spent almost his entire three-decade career within the walls of the House of Correction, starting as a guard and working his way through the ranks. When corrections department Commissioner William W. Sondervan went looking for someone to overhaul the chaotic prison in February, he sought out his old buddy.

"I needed someone who knew the place inside and out. And someone who meant business," said Sondervan. "So I called Hutch."

Sondervan said in a recent interview that Hutchinson has surpassed his expectations. "The change in prison culture before and after Hutch took over is nothing short of stunning," he said. "It used to be just like the streets in there, with the gangs. Now it's like a prison should be."

Hutchinson has a distaste for theoretical policy debates, dismissing them as "for politicians." He likens his job to that of a corporate manager with a single bottom line: maintaining order in the sprawling, castle-like prison built in the 19th century. In face-to-face contact with prisoners, however, he seems as much a congenial politician as a rigid disciplinarian.

"How you doing?" Hutchinson asked an inmate--a convicted murderer--as he strolled through the prison on a recent day. The man smiled, gap-toothed, replying, "Not all bad, Hutch," before trudging off to his work assignment, his feet linked by a thick chain.

The corrections officers and prisoners were all smiles and back-pats for their new warden as he showed a visitor one of the prison's recreation rooms. The room, lined with pay phones, contained shirtless inmates shooting pool and doing laundry while a small group gathered around a large-screen TV to watch "The Jerry Springer Show."

"As you can see, there is almost no tension here," he said.

A few hundred feet away, through several monitored gates, is the "old-timers" ward, where prisoners spend the last days of their life sentences.

"Some of these men were first incarcerated here when I started working 30 years ago. We sort of grew up together," he said, gesturing to three gray-bearded men, one missing several fingers, engrossed in a glacially slow card game.

As the centerpiece of his plan to restore order, Hutchinson is gradually developing an intelligence network that helps him keep on top of constantly shifting gang politics. This involves frequent questioning of corrections officers and inmate double agents--"rats," in inmate parlance.

The latest development, according to his intelligence, is that a black Muslim gang, the Sunni Muslims, is gaining the upper hand in the gang hierarchy. Some of Wise's remaining followers are attempting to assert themselves but appear to have no traction, said corrections officers interviewed. About a third of the prison is allied with the Sunnis in some fashion: for religious reasons, some for gangbanging, but many simply for protection, giving the Sunnis a diffuse network similar to Wise's former gang.

In a preemptive strike late last month, Hutchinson ordered a raid directed at the Sunnis. The action netted four cell phones and a small cache of drugs. A dozen inmates believed to be the gang's leaders were transferred to the Maryland Correctional Adjustment Center in Baltimore, known as Supermax, where inmates are kept in closet-size cells 23 hours a day.

The intelligence operation was born in the aftermath of Operation Ninety-Nine, when Hutchinson feared a riot. Inmates had threatened bloodshed over Wise's removal. But suddenly they realized that money, drugs and--most important--respect were up for grabs. The race for succession was on.

Hutchinson quickly established contacts within the prison's top gangs: Aryan Nation, the skinheads, Murder Inc., the Black Guerrilla Family, the Five Percenters, the Nation of Islam and the Sunnis. He now has five corrections officers working full time on intelligence gathering where before there were none.

"Every time we hear about anything, we bang them," Hutchinson said. "It's always a battle. When we take one group out, another starts to rise."

Hutchinson said the overwhelming majority of inmates have expressed gratitude for his removal of Wise.

"Most of these guys realize this prison could be their only neighborhood for the rest of their lives, and we just kicked out the neighborhood bully," he said.

Dennis Wise was a Baltimore drug kingpin with a formidable reputation on the streets. He was convicted of murder in Baltimore in 1979. He eventually ended up at the House of Correction in 1991. After a few years of good behavior and keen observation, Wise began his rapid ascent. His tool was the Inmates Advisory Committee (IAC), a 19-seat elected body of prisoners that forwarded inmate grievances to prison management. Members were given liberal access to much of the prison.

Wise and a small group of friends with a penchant for violence tapped inmates in each of the prison's 19 "districts" to run for the IAC. He ran campaigns for them, threatening harm against nonsupporters. All 19 won, by landslides.

With his IAC henchmen granted access to unmonitored parts of the prison, Wise began to smuggle drugs in and, using the prison's numerous pay phones, conducted drug business on the outside. The outside profit was used to recruit a handful of corrections officers. Soon they were smuggling for him. Four female officers worked as prostitutes, charging inmates $75 a session, which occurred in empty classrooms the IAC had access to. Wise also ran a bank that provided high-interest cash loans to inmates.

According to corrections officials, prison management at the time was aware of much of this but refused to act, believing that Wise kept the prison population in line.

"Dennis would tell prison management that he'd keep things under control in exchange for being allowed to keep his contraband," said a corrections officer who asked to remain anonymous. "To a degree, he did keep things in line. Most inmates either feared him or followed him."

At times, said several corrections officers interviewed, prison management even protected Wise.

"We used to try to write him up for various violations, but management would simply throw them away," one officer said.

Hutchinson agreed, though he was hesitant to name names: "Let's just say prison management allowed themselves to be manipulated."

One day in February, the IAC was summoned to a rare early morning meeting with prison officials in the House of Correction's chapel. Before they knew what was happening, they were in straitjackets and shackles aboard a van bound for Supermax.

Wise was transferred to a prison outside Flagstaff, Ariz., in March. Eventually, 32 other members of his gang were transferred out of the House of Correction. Two corrections majors, three captains, nine lieutenants and 18 officers thought to be in league with Wise were transferred or fired. The IAC was disbanded.

George B. Brosan, deputy secretary of the Department of Public Safety and Correctional Services, said that though gangs are trying to emulate Wise's reign, it is Hutchinson who is in control.

"The new warden means business," he said.