Chelsea Manning, Iranian extortionists, and Hillaryland’s original hacker—they’ve all been targets for prosecutors that now work for Team Mueller.

As special counsel Robert Mueller’s probe has quietly chugged along, outraging the president and encircling some of his top campaign officials, the investigation has slowly grown. When Mueller first started his investigation into potential coordination between the Trump campaign and the Kremlin, he brought on just over a dozen seasoned prosecutors—some from inside the Justice Department and others from private practice—to work on his team.

In the past six months, the number of prosecutors working on cases he has brought has expanded significantly, with new additions casting light on the special counsel’s potential priorities and focuses. Court filings show that at least half a dozen new names are participating in Mueller’s work, all current Justice Department prosecutors. Their backgrounds vary widely, from prosecuting violent crimes to cyber attacks.

Sol Wisenberg, who worked on Ken Starr’s independent counsel investigation of the Clinton White House, told The Daily Beast that the expansion of Mueller’s probe was to be expected.

“I don’t think it’s unusual at all,” he said. “That’s what happened with us. You get more cases or your cases become more complex, you need more prosecutors and you need more agents.”

“They wouldn’t bring them on if they didn’t need them,” he added. “They’re not bringing them on for grins. There’s work there that needs to be done or they would not be bringing them in.”

Ryan Kao Dickey

Of all of Mueller’s new prosecutors, Dickey—who joined the special counsel’s team last November—may have the experience that hits closest to home: He worked on the prosecution of Romanian hacker Marcel Lazar Lehel, known as Guccifer. Lehel hacked Sidney Blumenthal, a longtime confidante and ally of Hillary Clinton, and released emails showing she had used a private email address as secretary of state. His victims also included former secretary of state Colin Powell, Daily Beast founder Tina Brown, and actor Jeffrey Tambor. After Guccifer’s incarceration—a judge sentenced him to 52 months in prison—another hacker took up his mantle, going by the moniker Guccifer 2.0 and targeting the Democratic National Committee in the lead-up to the 2016 presidential election. The Daily Beast reported exclusively in March that Guccifer 2.0, who communicated with Trump ally Roger Stone and took credit for giving the hacked DNC emails to Wikileaks, is actually a Russian intelligence officer.

“He’s young,” said defense attorney Edward MacMahon of Dickey, “but he’s obviously very steeped in the world of the internet. He’s very steeped in everything going on with computer intrusions and how that works.”

MacMahon, who has squared up against Dickey in court, said the prosecutor is an expert in all things cyber.

“He doesn’t play games,” MacMahon said.

Timothy Belevetz, who worked alongside Dickey as an assistant U.S. attorney for a time, said he has “a fairly relaxed and personable style.”

“They’ve got their core group of prosecutors who are working for the SC, then they brought Ryan on, I suspect, because of his background with computer crimes issues, cyber issues,” Belevetz said. “I don’t know all the evidence the government has or all the facts of the case, but my guess is that there is some significant component of computer use that relates to the alleged offenses that they believe he would have some special background and some special skills regarding.”

Dickey is working on the prosecution of the Internet Research Agency, a Russian troll farm that sowed division in the American electorate during the 2016 campaign.

Heather Alpino

Alpinio graduated from Harvard Law School just four years ago, according to her LinkedIn profile. Since then, she has taken a position in the Counterintelligence and Export Control Section of the Justice Department’s National Security Division. In her time there, she has worked on cases with geopolitical ramifications, including the prosecution of a British national who conspired with an American to ship lab equipment to Syria, in violation of U.S. law. The equipment included tools to detect chemical weapons, according to a press release from ICE, which worked with the Justice Department on the case.

Alpino also worked on the prosecution of two Iranian nationals for a computer hacking scheme. The pair allegedly stole tens of thousands of people’s names and credit card numbers, and also tried to extort their victims. And she worked on the successful prosecution of Turkish national Hamza Kolsuz, convicted in 2016 for illegally trying to export guns to Turkey.

Alpino is also working on Mueller’s prosecution of the IRA.

Jonathan Kravis

Kravis, who has extensive experience prosecuting public corruption cases, worked in the White House Counsel’s office during the Obama administration as associate counsel to the President. And during that time, he got to know another key player in the Russia probe: Emmet Flood, who joined the White House legal team in May to help handle issues related to the probe. While he was in the White House Counsel’s Office under Obama, according to a 2009 ethics waiver, Kravis was responsible for liaising with the representative for former President George W. Bush. Flood was that representative.

Kravis also clerked for Justice Stephen Breyer and Judge Merrick Garland. But his record isn’t one of partisanship; he worked on the prosecution of Chaka Fattah, a Democratic representative from Philadelphia who was convicted for using government money to pay for his personal and campaign expenses. In 2016, a judge sentenced Fattah to ten years in prison.

Another high-profile case was the prosecution of corrupt Drug Enforcement Administration agent Artemis Papadakis, who last year pleaded guilty to stealing money recovered for victims of fraud.

Jeffrey Miller, a Philadelphia criminal defense attorney who once squared off against Kravis, told The Daily Beast he had no complaints about him.

“I would say he is very businesslike, definitely reserved, bright, doesn’t engage in what I call small talk, he doesn’t get into silly talk or nonsense talk,” Miller said. “He’s all business. Serious, bright, focused on the legal thing, not verbose. I have nothing negative to say about him. He was not disingenuous, he was not sarcastic, I did not find him to be incompetent at all.”

Kravis is working on the IRA case, along with Alpino and Dickey.

Uzo Asonye

For the contentious prosecution of former Trump campaign chairman Paul Manafort, Mueller has enlisted the help of Uzo Asonye, an assistant U.S. attorney in the Eastern District of Virginia. Defense attorneys who work in the district told The Daily Beast that Asonye is liked and well-respected, viewed as an honest broker and an expert on the ins and outs of the Alexandria courthouse where Manafort is facing charges.

“He’s hard-charging but he’s smart,” said one defense attorney, who spoke anonymously to keep his comments from coloring his relationship with Asonye. “He works really hard.” The attorney added that Asonye, who started working with Mueller in May, is best known for his work on fraud and financial crimes. He is the deputy chief of his office’s Financial Crimes and Public Corruption Unit, according to his LinkedIn.

“He’s skillful as well as being fair,” said defense attorney Thomas Abbenante. “I find him very easy to work with. He understands his role, he understands my role, and we’ve been able to work out very difficult cases together.”

Asonye has taken heat from the right for giving $900 to Hillary Clinton’s unsuccessful presidential campaign in 2009.

Kathryn Rakoczy

Rakoczy’s role on Mueller’s investigation—made public in a June 22 court filing—has raised some questions in Washington legal circles. An assistant U.S. attorney in the district of D.C., Rakoczy is best known for her work on violent crime cases. She focused on misdemeanors until about eight years ago, and then shifted to primarily prosecuting D.C. street crime. A Washington criminal defense attorney familiar with her work, who spoke anonymously to prevent tension between himself and Rakoczy, said her work for Mueller has generated some head-scratching, since Mueller isn’t investigating any violent street crimes.

The Washington Post reported in June that Mueller may have added the career Justice Department prosecutors to the IRA prosecution team so they can take it over once the special counsel probe winds down. It’s unlikely any of the 13 Russian nationals indicted in that case will be extradited to the United States, and legal proceedings could drag on for years.

Deborah Curtis

Curtis, another prosecutor working on the IRA case, comes from the DOJ’s National Security Division, where she is deputy chief of the Counterespionage Section. From that perch, she has had a role in some of the DOJ’s most electric prosecutions, including going after a Chinese company accused of sanctions-busting on behalf of North Korea and prosecuting Stewart David Nozette, a prominent American scientist who pleaded guilty to spying for the Israeli government. She also worked on the prosecution of Chelsea Manning, according to notes on grand jury proceedings that one witness took and then posted online.

And Curtis’ work meant she crossed paths with one of the most high-profile lawyers representing a client who has been enmeshed in the Mueller probe: Abbe Lowell, Jared Kushner’s attorney. Curtis worked on the prosecution of former State Department contractor Stephen Jin-Woo Kim. Lowell represented Kim when he was prosecuted for—and ultimately pleaded guilty to—disclosing classified material to a Fox News reporter.

There’s a bit of an irony here: While Mueller’s critics have accused the probe of leaking, he's brought on a seasoned leak prosecutor.

The new attorneys bring additional breadth and depth to Mueller’s team, as well as experience working on complex and politically sensitive matters. It’s no surprise Mueller’s team would be quietly fleshed out, even as it faces the noisiest criticism.