The season 3 finale of "The White Lotus" recently aired — with the episode featuring the "pong pong tree," a plant with fruit so poisonous that it is nicknamed "the suicide tree." 

While viewers may think this is just a plot device fabricated for dramatic effect, the tree, its fruit and its killer seeds are real.

Native to Southeast Asia, the Pacific Islands and parts of Australia, Cerbera odollam – also known as the pong pong tree – belongs to the dogbane family, which also includes other poisonous plants, according to a National Geographic report.

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The pong pong tree produces white, fragrant flowers as well as a fruit similar to an apple. 

At the core of the fruit is a highly toxic seed, WebMD noted.

The seed contains concentrated amounts of cerberin, a bitter-tasting, poisonous substance that can be deadly without immediate medical care.

Cerberin is a cardiac glycoside, an organic compound that slows down heart function.

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The tree was involved in over 500 deaths between 1989 and 1999, according to WebMD. 

When ingested, cerberin is absorbed into the bloodstream from the stomach, where it can begin to slow a person's heart rate in as little as an hour, National Geographic stated. 

Initial symptoms may include nausea, vomiting and diarrhea, escalating to irregular heart rhythms or heart failure.

"It will basically override the polarization within the body that's required for the heart muscle to contract and relax," said Owen McDougal, a professor of chemistry and biochemistry at Boise State University, in the report. 

"Without the impulse and relaxation phases, the heart muscle just stops working."

He added, "It's not a desirable way to go."

Each person's reaction to the toxin will depend on a variety of factors, including age, gender, size and other medical conditions, the report stated.

Most exposures will cause death within three to six hours, WebMD noted, but some cases may be treatable depending on severity and amount of time since ingestion.

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Some studies have suggested that getting immediate medical attention could reduce mortality to 12%, per the above source.

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"Eating Cerbera odollam seeds is extremely dangerous and should be avoided at all costs," the WebMD report says. 

"If you’re ever in a situation where you accidentally eat these seeds, call the emergency services immediately."

James Dmello awoke at 3 a.m. Saturday to watch the televised funeral Mass for Pope Francis at St. Peter’s Square in Rome.

Dmello, 57, of suburban Cary, was overcome with emotions and immediately knew he and his wife, Anne, had to be present for a Mass memorializing the pope because "if he was for us, then we have to be for him."

“It was too much, like, I couldn’t control myself. I woke up 3 in the morning and nonstop until it got over, I was there the whole Mass,” Dmello said.

The Dmellos were among nearly 800 parishioners who attended a Saturday evening memorial Mass for Pope Francis at Holy Name Cathedral, 735 N. State St., on the Near North Side.

The couple revered the pontiff for his humility and the connections he made across the world.

“As we all know, he was ‘people’s pope,’ and for me, for us, it’s like ‘papa pope, papa Francis,’” Dmello said. “So, he was dear to all people, very down to earth. You’ve never seen any of that kind of person, so humbled.”

At St. Thomas the Apostle Catholic Church, 5472 S. Kimbark Ave. in Hyde Park, Deborah De Rosa and Renee Blanchard, were bidding a final farewell to Francis, 88. They are immigrants, and they said Francis, being the first Latin American pope, was "huge and important" to them.

Blanchard said Francis "rejuvenated" the church with his teachings, and De Rosa noted his "compassion for the poor."

"I was so sad when he died," De Rosa said. "I knew he was going to die soon, but the reality of it, it just hurts."

According to Vatican estimates, some 250,000 people flocked to the funeral Mass at the Vatican, and 150,000 more lined the motorcade route through downtown Rome to witness the first funeral procession for a pope in a century at about 3 a.m. Chicago time. 

They clapped and cheered “Papa Francesco” as his simple wooden coffin traveled aboard a modified popemobile to St. Mary Major Basilica, about 3 miles away.

Simple funeral reflected ‘people’s pope’

Francis planned the funeral when he revised and simplified the Vatican’s rites and rituals last year. His aim was to emphasize the pope’s role as a mere pastor and not “a powerful man of this world.”

Michael Canaris, an associate professor at Loyola University Chicago, said there were a number of unique aspects to Francis’ funeral, including simplifying liturgical rites, titles and prayers for much of the service.

The casket — which is generally stacked in three layers “Russian doll style,” as Canaris put it — was also reduced to a simpler wooden casket, according to Canaris. Francis’ tomb will simply be marked “Francis” and was converted from a closet that formerly was used to store candelabras.

“These traditions develop over hundreds of years, so even minor tweaks to the process carry a lot of weight both symbolically and also theologically,” Canaris said. “You can see with these movements toward a very simple tomb. He had said he wanted to be buried how a normal Christian would be, not a body displayed on a dais to venerate it.”

The Rev. Larry Sullivan, who delivered Saturday’s Mass at Holy Name Cathedral, noted that Francis had embodied one of Sullivan’s favorite sayings, “Preach the gospel often, use words when necessary.”

“The way that Pope Francis was able to really, sincerely reach out to others — whether they were children in need, or whether they were handicapped, or whether they were incarcerated or poor, Pope Francis had a way of seeing the face of Jesus in every single person that he met,” Sullivan said.

“As powerful as the words of Pope Francis were, it is those images of him reaching out, and gathering in, that really signify the true impact of his papacy upon our church,” Sullivan said.

It’s a stark contrast from popes of the past who had lived in luxury and some whose tombs were adorned with Michelangelo’s work.

“He saw the church not as a fortress fighting against the ills of the world, but more of a field hospital binding the wounds of an aching humanity, and that’s really present in much of what he tried to embody with his life, ministry and teaching,” Canaris said. “This is a continuation of those gestures rooting him in humanity.”

Contributing: Associated Press