"Three capital murder suspects ... it was a dope rip in Lee County."

Miguel Dominguez is briefing his fellow deputy U.S. Marshals about the impending mission, as the team waits in a Houston Police Department parking lot for a couple of Texas Rangers driving in from Austin.

The Rangers have "good info," he says, but the team already has "guys on the house" with HPD "standing by." Dominguez shows fellow Deputy Marshals Alfredo Perez and Don Snyder pictures of the three suspects.

"Hopefully, it'll be one-stop shopping and we'll get all three in custody," he says.

The U.S. Marshals Service has been the federal government's manhunters since 1789, and they have no problem reminding you about it.

"The Marshals job is to grab the body," said Richard Hunter, the chief deputy U.S. Marshal for the Southern District of Texas. "And we're the best in the world at it."

Fox News was given exclusive access by the U.S. Marshals Service, riding along as they hunted down some of the most dangerous criminals in the country, including those three murder suspects.

It is all part of "Operation Triple Beam."

OTB is a 90 to 120 day operation led by the U.S. Marshals Service in cities around the country, which, according to the USMS, "Brings together federal, local, and state law enforcement, to focus on specific areas impacted by specific gang violence, while targeting the most violent gang members and organizations."

The latest mission, which concluded in Houston on Thursday, netted 341 warrants cleared by arrest, 220 gang-affiliated arrests, 62 firearms seized, nearly $60,000 in currency, and narcotics with a street value of over $1 million.

That makes Houston's OTB one of the most successful in the history of the operation. Since 2010, the U.S. Marshals have used the operation to make more than 6,000 arrests across the country, along with the seizure of 1,500 illegal firearms, more than $1.5 million in cash and over $6 million in narcotics. The officials involved in the operation say it's a classic case of local and federal law enforcement agencies cooperating to get the job done.

"The Marshals Service is just a phenomenal partner for the big cities in this country," Houston Chief of Police Art Acevedo told Fox News. "When you think about the resource challenges we have at the state and local level, they are a great force multiplier ... we are joined at the hip."

Acevedo acknowledged that cartel activity at the southern border affects his city directly. "We have people and drugs that come north, going south we have guns and cash," he said.

However, the Houston Police Chief strikes an unapologetically moderate tone when it comes to policing undocumented immigrants.

"I coined a phrase at the Houston PD: we chase crooks not cooks," he said. "If ICE wants to work with us to go after our hardcore gang members, MS-13. ... If they want to help us and work with us going after those bad actors we're all for it. Now, if they want to go to the local Home Depot looking for people that are day laborers trying to get work ... let's focus not on low level. You are not helping me with my violent crime problem when you get the nanny down the street or the cook in the kitchen."

Acevedo also told Fox News that ICE has been very cooperative on that front.

The raid on the house with the three murder suspects, meanwhile, was a swift operation.

Radio traffic crackled from the surveillance units surrounding the house the Texas Rangers tagged as their hideout.

"He's moving," a voice squawked over the channel.

The team swept out in a flash, with multiple law enforcement vehicles rolling through the streets of Houston. They landed on Suspect One in minutes, in a show of overwhelming force. He exited his car without a fight, hands in the air and in custody.

Suspect Two was caught just as quickly.

There was no time to waste with Suspect Three. The Marshals believed the suspect was still in the home under surveillance, perhaps wondering why his accomplices had gone dark.

Deputy Marshals, Houston PD, state police and sheriff's deputies surrounded the house.

"Police!" they screamed as they banged on the door. Suspect Three came out with arms raised in the air.

Within 20 minutes, the manhunters had their three capital murder suspects in custody – and all before lunchtime.