The 7 Biggest Bombshells from 'The Price of Glee'

The Price of Glee debuted on Monday, pulling back the curtain on Glee's dark behind-the-scenes drama, including the sudden deaths of stars Cory Monteith, Naya Rivera and Mark Salling.

Although the hit Ryan Murphy-helmed FOX show went off the air in 2015, it remains a highly discussed topic. Investigation Discovery's three-part docuseries attempted to shed a new light on that conversation by interviewing relatives, friends and publicists of Glee cast members, as well as former crew members and journalists who covered the television phenomenon.

Notably missing were any of the show's stars, including Kevin McHale, who said he and his fellow castmates purposely chose to "have nothing to do" with the series.

McHale's costar Chord Overstreet was less diplomatic, calling The Price of Glee "bulls---" and adding, "I think anybody that knows anything about that show and experienced it doesn't have anything to do with [the docuseries], from what I know."

Here are seven of the biggest takeaways from The Price of Glee.

Cory Monteith's addiction struggles began in his teenage years — and he purposely hid it from the public until the end of season 2

During Glee's early days, Monteith was concerned about maintaining a clean image, according to his friend Frederic Robinson.

"When he got the part, he was supposed to be this good kid playing this role. He didn't want his past getting out," Robinson said. "The beginning of his success with Glee, we were really being told, 'Don't let it out that he's got the drugs and alcohol problem.'"

But while it may have been a secret to the public, Monteith had no problem disclosing it to his close friends, including his roommate Justin Neill.

"When Cory moved in, it was New Year's Eve 2008. The next day, he said it in such a flippant manner, something about drug use and he wanted us to know right away that he had a past, he's sober now and that this is a big part of his life," Neill recalled.

According to the docuseries, Monteith started skipping school to use drugs at age 13, just a few years after his parents got divorced. He went on to attend a dozen schools, including programs for troubled teens, and often stole "large sums of cash" from his family. At age 19, his mother and friends staged an intervention, leading him to enter a drug rehab program in 2001.

It wasn't until the end of Glee's second season that Monteith went public with his struggles, admitting in an interview that he wanted to share his past so people didn't assume he was exactly like his all-star quarterback character Finn Hudson.

"I feel like I had to step in at some point and relate to people with my experience and where I come from," he said.

Monteith's publicist Lesley Diana also said he wanted to go public in order to help others: "Cory wanted to help others who perhaps were in that same situation to show them that you can come out on the other side and do well in life."

Multiple people "didn't understand" Cory Monteith and Lea Michele dating

Just as Lea Michele and Cory Monteith's characters dated on screen, the pair also developed an off-screen connection — but not everyone supported the romance.

"I did not understand the two of them together," said Garrett Greer, an assistant to the executive producer of Glee. "I had friends who lived in New York and grew up with Lea, so I was very aware of her reputation. She had a rep for being a little bit difficult."

"I found that interesting that they ended up together. I was really very surprised," added seasons 1 and 2 set decorator Barbara Munch.

Cory Monteith once said he "wouldn't wish fame on my worst enemy"

Former roommate Neill said Monteith struggled with fame as Glee's popularity skyrocketed and the show's fandom intensified.

"There was a period where it seemed Cory was getting more and more isolated," he recalled. "He just got to the point where he just hated fame. [He said], 'I'm just so tired, I want to rest for a bit. I'm sick of singing of these songs,' and I remember him specifically saying, 'I wouldn't wish fame on my worst enemy.'"

Neill continued, "I'd seen the fame, but I didn't realize how hard it was for him until then. I think with that level of fame, you lose sight of who you are. To every single person, he wasn't Cory anymore. He was now Finn. We just knew he wasn't in the best place."

Neill added in the second episode of The Price of Glee that Monteith became frustrated with Glee's demanding schedule and wanted more freedom with his career. "He had to turn down movies, he was becoming more neurotic and isolated," he said.

However, Neill did also note that, "As much as he didn't like fame, he knew how lucky he was. He never took it for granted."

The cast became competitive about who could amass the biggest following on social media

As the show became a hit, social media was on the rise, and the Glee stars were poised to dominate emerging platforms — but the competition wasn't always friendly, according to the docuseries' commentators.

"I would oftentimes see the actors gathered talking about how many people they acquired as followers, and it was a competition," said season 3 hair department head Dugg Kirkpatrick.

"In the beginning, they had to tweet every day. It was Lea who really had the numbers," recalled Kirkpatrick.

Journalist Andy Swift said, "The fighting began almost immediately."

A crew member recalls Cory Monteith's swift relapse and "path to destruction"

Hair department head Kirkpatrick recalled one of the final times he saw Monteith and the troubling story the actor allegedly told him during a haircut.

"He wasn't drinking, he didn't have any drugs in his system," Kirkpatrick said. "And then the very last couple of days that I saw him, he was different. He was under the influence of alcohol."

"He said he was at a party and he hadn't been drinking and wanted to have a drink but knew he shouldn't," he continued. "And he was told by a certain cast member that same night, 'You know, if you want to have a drink, you should have a drink. I'll be here, you can always trust that I will be here for you.'"

"In my opinion, you would never say that to someone who is sober," Kirkpatrick said. "And so that confused him and kinda made him mad, and so he started drinking because he was given permission by somebody.... I'm not gonna mention names because I wasn't there and I didn't hear the person say it."

He added of Monteith: "He resented it, but also he took the direction. I think it set him on a path to destruction."

Glee lost not only 3 stars but also several crew members during its run

As fans know, Monteith, Rivera and Salling all died prematurely under tragic circumstances.

Monteith was 31 when he died of a heroin overdose on July 13, 2013. Rivera (who portrayed cheerleader Santana Lopez) died at age 33 on July 13, 2020, after she accidentally drowned during a boating trip with her son at a Southern California lake. Salling, who played jock Noah "Puck" Puckerman, died at age 35 in an apparent suicide weeks before he was scheduled to be sentenced to prison for possessing child pornography.

Less well-known are the multiple crew members who died during Glee's run.

J.A. Byerly, a rigging gaffer for the show's first five seasons, revealed in the docuseries his brother died by suicide at the end of season 6, seemingly because he had become overwhelmed by the show's demands.

"On the rigging crew, you are constantly working daily. Most of our timecards are at 72 hours.... We don't win the Oscars, we don't win the Emmys, but we're the ones who make it happen. The intenseness of the show, I think, got to my brother," he said. "The pace and the pressure that was put on you to deliver ... I blame it on that show."

Jim Fuller, who was in charge of the second team and background actors, died after suffering a heart attack at 41, while production assistant Nancy Motes died by suicide.

The docuseries also noted that a "lead prop guy" named Paul died while jogging after suffering a massive heart attack, and another one of the "main stand-ins" who provided coverage for star Matthew Morrison suddenly died with few details known aside from the death being related to a "car fire."

"This was a big set, a lot of people," said Christopher Baffa, the director of photography for Glee's first three seasons. "But to lose so many people, so quickly, you see a pattern forming there that to me is still unbelievable. Was that Glee or just the industry? I don't know."

Naya Rivera's dad warned her about the dangers of boating before her drowning

Rivera's dad George recalled the last time he spoke to his daughter, which happened to be via FaceTime shortly before she died.

"I get a sinking feeling cause we've been boating forever," he said. "I was FaceTiming with her trying to talk her through the pitfalls of trying to anchor your boat. First of all, I said, 'Naya, you're on a pontoon boat, that's not a boat ... why are you on a pontoon boat?'"

"I said, 'Do not jump off that effin' boat. If you've got an anchor, you can anchor it, but do you know how to anchor it? We went through a couple iterations like that and then the FaceTime call hung up and that was the last time I talked to her," he added.

After receiving a call from authorities about his daughter, George began the multi-day drive from Knoxville, Tennessee, to Ventura County, California — but even though he considered his daughter a "really good swimmer," he instinctively feared the worst.

"I knew immediately when I got the phone call in Knoxville that it was over with," he said. "You don't find a drifting, 5-year-old child asleep on a boat at the end of a lake without his mother and have any hope. I had no hope."

Speaking about his grief now, George said, "You don't process it ... I don't know what everybody else does but for me, it's as fresh today as it was two years ago."

He later added, "[Naya] knew she was on a really good show with a lot of tragedies. Don't know if you can equate that to fame, but I think it has something to do with it."

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All three episodes of The Price of Glee are now available to watch on ID and discovery+.