Former President Trump's hush money trial is scheduled to start Monday, with several key players involved in the case over illegal payments to an adult film actress in 2016.

The big picture: The historic indictment against the former president regarding payments to Stormy Daniels will be the first of his four criminal cases to go to trial.

• The presumptive GOP presidential nominee faces 91 criminal charges in four separate jurisdictions and denies any wrongdoing.

Driving the news: In addition to the expected key players, Judge Juan Merchan, who is presiding over the case, said Monday that dozens of others could also be involved in the trial, CNN reports.

• Merchan said that members of Trump's family, ex-Trump lawyer Rudy Giuliani and former Trump adviser Steve Bannon could all be involved in the trial.

Here are the key players in the case:

Former President Trump

Trump has pleaded not guilty to 34 felony counts stemming from allegations he falsified business records to cover up the payments.

• While a candidate in the 2016 presidential election, Trump allegedly told his former lawyer Michael Cohen to send Daniels hush money. The payment was recorded as legal expenses.

Michael Cohen

Trump's former personal attorney Michael Cohen alleges the former president directed him to pay $130,000 in hush money to Daniels to keep her from going public about an alleged affair with Trump. He denies both claims.

• In 2018, after the alleged hush money to Daniels emerged, Cohen initially said he paid with his own money and that neither the Trump campaign nor the Trump Organization reimbursed him.
• Cohen pleaded guilty in 2018 to federal charges and received a three-year prison sentence related in part to the payment to Daniels.
• He testified last year before the grand jury that voted to indict Trump.
• Cohen is also a key witness in New York Attorney General Letitia James' $250 million lawsuit alleging that Trump, his eldest children and the Trump Organization committed years of financial fraud.

Alvin Bragg

Manhattan District Attorney Alvin Bragg is at the forefront of the historic indictment against Trump.

• A Democrat who became Manhattan's first Black district attorney in 2022, Bragg inherited the years-long Trump probe from his predecessor.
• Bragg has repeatedly been the target of Trump's fury over the investigation and faced a probe by House Republicans over the matter.
• The DA's office under Bragg requested a gag order against Trump this month, which Judge Juan Merchan granted and then expanded at the DA's request.

Judge Juan Merchan

Acting New York Supreme Court Justice Juan Merchan has handled several high-profile prosecutions, including some involving Trump's inner circle.

• Merchan declined to recuse himself from the case after Trump's lawyers requested he do so amid allegations of bias. They have repeatedly tried to push back the trial earlier set for March 25.
• In a recently denied request, Trump's lawyers were seeking an indefinite delay, so they could remove Merchan as presiding judge and challenge several of his rulings.
• Trump himself has lashed out at the judge and taken aim at his daughter, Loren, who has done Democratic political consulting work. Merchan granted and later expanded a gag order requested by prosecutors to stop Trump from attacking people involved in the case and their families.

Flashback: Merchan oversaw the criminal tax fraud case against the Trump Organization, in which a jury found two companies from the organization guilty on 17 counts. In a separate case, Merchan sentenced the firm's finance chief to five months in jail and five years of probation for tax fraud.

Stormy Daniels

Daniels, whose real name is Stephanie Clifford, said she was paid by Cohen before the 2016 presidential election to stay silent about her alleged affair with Trump.

• Daniels, an adult film star and director, met with prosecutors from Bragg's office before Trump's indictment. She told The Times that Trump's indictment was "vindication" and she's "fully aware of the insanity of it being a porn star."
• She says she was 27 when she met Trump, then 60, at a celebrity golf tournament in July 2006 and the affair occurred after that, which the former president denies.

Trump's attorneys

Todd Blanche, a former assistant U.S. attorney in the Manhattan U.S. Attorney's Office, was brought on as Trump's lead counsel in the case.

• Less than two years ago, Blanche was registered as a Democrat in New York and a partner at a prestigious Wall Street law firm. He's now registered as a Republican in Florida and has his own firm, the New York Times reports, adding the career move has left his former colleagues baffled.
• Blanche previously represented Trump's former campaign chair Paul Manafort as well as Igor Fruman, a Rudy Giuliani associate who pleaded guilty in a campaign finance case brought by the Manhattan U.S. Attorney's Office.
• Trump is also represented in the case by Susan Necheles, who previously served on the defense team in the Trump Organization tax fraud trial.

Trump aides

Some of Trump's former White House aides could be called as witnesses at the trial. They include:

• Former White House communications director Hope Hicks, who was one of Trump's closest and most loyal aides before she resigned in March 2018;
• Kellyanne Conway, the former Trump campaign manager-turned-spokesperson; and
• Rhona Graff, who was senior vice president at the Trump Organization and worked at Trump Tower for nearly three decades.

Karen McDougal

The former Playboy model, who could be a witness in the trial, is believed to be the second woman paid hush money over an alleged affair with Trump.

• McDougal is believed to have received $150,000 from American Media Inc., the owner of the National Enquirer, for the rights to a "catch and kill" story about the affair.
• McDougal filed a lawsuit in 2018 against AMI to void the legal agreement that required her to stay quiet about the affair, which McDougal claimed took place in 2006. They subsequently reached a settlement agreement.

David Pecker

Prosecutors alleged in the indictment that Pecker, the former CEO of AMI, met with Trump in 2015, agreed to help his campaign and vowed to look out for negative stories about Trump and publish them about his competitors.

• Pecker, who may also appear at the trial, was allegedly involved in some of the "catch and kill" payments outlined by prosecutors.
• Prosecutors also alleged that Trump invited Pecker to dinner at the White House in the summer of 2017 to "thank him for his help during the campaign."

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