Matthew Perry’s death struck fans worldwide — and also opened a months-long investigation.

The beloved Friends actor died after an accidental drug overdose on Oct. 28, 2023. An autopsy later showed Perry died from acute effects of ketamine, in addition to other contributing factors such as drowning, coronary artery disease and effects from buprenorphine, a medication used to treat opioid use disorder.

Over six months after his death, the Los Angeles Police Department was conducting a formal investigation into how the actor obtained the ketamine after the Los Angeles County Medical Examiner-Coroner closed their investigation in December 2023.

On Aug. 15, five people — including two doctors and Perry’s personal live-in assistant — were arrested on charges in connection with the actor’s death.

Jasveen Sangha — who United States Attorney Martin Estrada said is referred to as “The Ketamine Queen” — and Dr. Salvador Plascencia are both currently facing charges in the case, the Department of Justice announced. Perry’s assistant Kenneth Iwamasa was also charged — and has already pleaded guilty — alongside Erik Fleming and Dr. Mark Chavez, according to the DoJ.

“These defendants took advantage of Mr. Perry’s addiction issues to enrich themselves,” Estrada said. “In the end, these defendants were more interested in profiting off Mr. Perry than caring for his well being.”

Here’s a complete timeline of the investigation into Matthew Perry’s death and why five people are seeing their day in court because of it.

October 28, 2023: Matthew Perry dies of an accidental drug overdose

Perry was found dead at his Los Angeles home at 54 years old.

“We are heartbroken by the tragic loss of our beloved son and brother,” his family said in an exclusive statement to PEOPLE. “Matthew brought so much joy to the world, both as an actor and a friend. You all meant so much to him and we appreciate the tremendous outpouring of love.”

An LAPD spokesperson told PEOPLE that first responders arrived on the scene around 4:07 p.m. and found an “adult male patient” already deceased. “The patient was found by a bystander who had repositioned the victim where the head was out of water” in a freestanding jacuzzi. The firefighters on the scene pulled Perry out to discover he was dead.

December 2023: Matthew Perry’s cause of death is determined

Two months later, Perry’s cause of death was revealed in an autopsy obtained by PEOPLE. The 17 Again actor died from acute effects of ketamine with drowning, coronary artery disease and buprenorphine effects also listed as contributing factors. The death was ruled accidental.

The autopsy stated that Perry was “reportedly clean for 19 months” and was receiving a ketamine infusion therapy, with his latest treatment taking place “one and a half weeks” before his death.

His final treatment did not, however, contribute to his death as the coroner noted that “ketamine’s half-life is 3 to 4 hours, or less.”

January 9, 2024: The investigation into Matthew Perry’s death is officially closed

A few weeks later, the LAPD confirmed to PEOPLE they would no longer be looking into Perry’s death. The Los Angeles County Medical Examiner-Coroner also confirmed the case was “closed.”

May 21, 2024: The Los Angeles Police Department is investigating the circumstances surrounding Matthew Perry’s death

Though the LAPD announced they closed their investigation in January, just four months later, a new investigation came to light that involved them working with the California branch of the Drug Enforcement Administration to determine the source of the ketamine that led to Perry’s death.

At the time, authorities had conducted several interviews, but no arrests had been made.

June 25, 2024: A law enforcement source tells PEOPLE “multiple people” should be charged in association with Matthew Perry’s death

While the investigation was ongoing, a law enforcement source told PEOPLE that it was “nearing its conclusion,” and police believed “multiple people” should be charged.

However, the source added that the U.S. Attorney’s Office would make the final decision on whether or not to press charges. The same day, the office responded “no comment” to PEOPLE’s request for comment.

August 15, 2024: Matthew Perry’s personal assistant and doctors are arrested on charges surrounding his death

Five people were arrested on Aug. 15 in association with Perry’s death, including his personal assistant, Kenneth Iwamasa. The first two defendants named to the case were Jasveen Sangha — who United States Attorney Martin Estrada claimed is referred to as “The Ketamine Queen” — and Dr. Salvador Plascencia.

Sangha is charged with one count of conspiracy to distribute ketamine, one count of maintaining a drug-involved premises, one count of possession with intent to distribute methamphetamine, one count of possession with intent to distribute ketamine and five counts of distribution of ketamine, the Department of Justice announced.

Plascencia, who is a licensed physician, was charged with one count of conspiracy to distribute ketamine, while the three other defendants — Iwamasa, Erik Fleming and Dr. Mark Chavez — were charged separately.

According to the DOJ, Fleming pleaded guilty to one count of conspiracy to distribute ketamine and one count of distribution of ketamine resulting in death, while Chavez will plead guilty to one count of conspiracy to distribute ketamine.

Iwamasa pled guilty to one count of conspiracy to distribute ketamine causing death, after he “repeatedly” injected Perry with ketamine “without medical training,” including on the day Perry died, according to the DOJ.

The former assistant and Fleming could face up to 15 to 25 years in prison after pleading guilty, while Chavez could face up to 10 years in prison. If found guilty, Sangha will serve a mandatory minimum of 10 years in prison and a possible life sentence.

Estrada has alleged that the five defendants “took advantage” of Perry for their own “profit.”

According to the DoJ, Plasencia allegedly contacted Chavez – who was also a doctor and previously operated a ketamine clinic – to obtain the substance to sell to Perry. In text messages to Chavez, Plasencia allegedly discussed how much to charge Perry for the ketamine, stating, “I wonder how much this moron will pay” and “Lets [sic] find out,” the DoJ claimed.

The attorney also alleged that the defendants were aware of what the negative impacts on Perry’s health could be because of their choices. Estrada claimed the prosecution had found text messages in which Sangha wrote, “I wouldn’t do it if there wasn’t a chance of me making some money for doing this.”

Following Perry’s death, the defendants tried to “cover up” their involvement, Estrada claimed, adding that Sangha allegedly wrote in a text message to another defendant, “Delete all our messages.”

August 16, 2024: Matthew Perry’s stepdad Keith Morrison looks forward to “justice”

One day after federal investigators announced their charges, Perry’s stepdad Keith Morrison shared his gratitude to law enforcement for their investigation, saying that he hopes that “justice” will be carried out.

“We were and still are heartbroken by Matthew’s death, but it has helped to know law enforcement has taken his case very seriously,” the Dateline correspondent, said in a statement to PEOPLE for the Morrison family. “We look forward to justice taking its course and we’re grateful for the exceptional work of the multiple agencies whose agents investigated Matthew’s death.”

Morrison continued: “We’re hoping unscrupulous suppliers of dangerous drugs will get the message.”

If you or someone you know is struggling with substance abuse, please contact the SAMHSA helpline at 1-800-662-HELP