Warning: Major spoilers ahead.

On March 28, the producers of hit podcasts "Serial" and "This American Life" released "S-Town," a seven-part investigative series based in rural Woodstock, Alabama. In its first week, it topped 16 million downloads, a blockbuster by podcasting standards. Like "Serial," "S-Town" opens with a tipster asking a journalist to investigate a murder. But soon, the narrative pivots, and listeners are drawn into the heartbreaking story of one man and his lifelong struggle with mental illness.

John B. McLemore, an antique clock restorer and horologist, talks for hours with journalist Brian Reed, first on the phone and then in person when Reed travels to Alabama. Recordings with the eccentric, hyper-articulate McLemore reveal a passion for clocks, dedication to his elderly mother, and pride over the outdoor garden maze in his backyard—but also an obsession with climate change and the problems with Woodstock, which he calls "Shit Town, Alabama." As the podcast unfolds, a theme emerges: McLemore is struggling with depression. In the second episode, we learn McLemore died by suicide at age 49, leaving his friends and family (as well as invested listeners) devastated by the loss.

Depression is a complicated mental health condition, affecting more than 15 million U.S. adults annually. Symptoms can vary person to person, but frequently include deep sadness, lethargy, and feelings of worthlessness. Men are four times as likely to die by suicide than women.

In the final episode, Reed theorizes that McLemore may have been suffering from mercury poisoning, which has symptoms similar to depression. Regardless of whether that's true, "S-Town" sheds light on depression—particularly depression in men—in unprecedented ways. In between the engrossing, novelistic storytelling, the podcast teaches important lessons about recognizing depression symptoms and how to help someone struggling with mental illness.

Someone who is depressed may not always seem sad

Throughout "S-Town," McLemore ranted about the people in his town, police corruption, climate change, and other problems he saw in the world, but a close friend described him as mostly humorous and disgruntled. His anger and irritability, though, were hallmark symptoms of depression in men. "Depression tends to be more under-recognized in men," says Gail Saltz, MD, a New York City-based psychiatrist and author of The Power of Different: The Link Between Disorder and Genius. “Men are more likely to present looking angry and irritable, so they may be thought of as being aggressive or difficult people as opposed to depressed."

Speaking candidly about suicide is a major risk factor

McLemore spoke casually about his poor mental state, acknowledging that he would go through stages of depression where he was in a "tired, somber, and reflective mood." He also told Reed he planned to commit suicide one day. “He was so cavalier about it. He would dismiss your concern, laugh it off, and try to change the subject,” Reed said in the fourth episode. We also learn that McLemore kept a suicide note on file.

When somebody brings up sucide—even in a casual, or even humorous way—it’s important to ask more questions. "Ask them if they have a plan. And if they have a plan, ask them if they have the means," says Dr. Saltz. "If they answer 'yes' to all of those things, you should take them to the emergency room or call the police. It is okay for you to call the police if you believe them to be in danger."

In McLemore’s case, he did have a plan. And while some people may not have taken his repeated comments and threats seriously, it is important to seriously consider taking action. “People are very reticent and fearful of having someone brought in,” says Dr. Saltz. “But if someone is really discussing their death their death or their manner of death and they have the means, that is someone who is telling you they are at a very high risk.”

Sexuality plays a role

McLemore defined himself as "semi-homosexual." We learn more about his struggle with sexuality in an interview with a close friend, Olin, who he originally met on a singles' chat line for gay men. Olin explained that coming out as gay in a small, conservative town in the rural south may have been difficult, and possibly even dangerous, for McLemore. Olin also told Reed that McLemore tried to come out to his mother, but she left the room and never spoke about it again.

"Sexuality has a big impact on mental health," says Ben Michaelis, PhD, clinical psychologist and creator of oneminutediagnosis.com. "The notions that we have about who we are and who we’re going to be get put into us early on. So if who we are fundamentally contradicts that, there’s no doubt there will be gripes.”

In a heartbreaking revelation, Olin told Reed that McLemore was desperate for companionship, and a one-on-one relationship, something that he never fully had the chance to experience.

Depression affects how you perceive others’ feelings for you

At the beginning of "S-Town," McLemore told Reed he had few friends, and often felt alone. In truth, many people cared deeply for McLemore throughout his life, like his college professor, friends around town, fellow horologists, past love interests, and Tyler Goodson, the man who he treated like his own son.

"Depending on the severity of depression, it can create imagined apathy, it can create paranoia that people are out to get you, or have malice toward you," says Dr. Saltz. "Additionally, a conflict around one's sexuality, like John had, is significant stressor. In a way, depression can be self-loathing. If you hate that you are gay, and you cannot come to terms with that, that self-loathing can be projected outward into ‘every body feels the way about me that I feel about me.'"

If a depressed person refuses help, there's still more you can do

Friends tried to help McLemore cope with his depression throughout his life. In college, a professor sent him to a psychiatrist, who put him on antidepressants; McLemore stopped taking them because he didn't like how they changed his personality. A fellow horologist bought him a book on holistic remedies for depression, thinking that may be more his speed, and other friends at various points suggested seeking out help, but he always refused.

"To some degree, unconsciously, they may be making you feel helpless because they feel helpless,” says Dr. Saltz. “It’s a projection." So what can be done when a loved one refuses help?

Unfortunately, there's no one thing you can do to be sure a depressed person gets the help they need. In a case like McLemore's, Dr. Michaelis says it may help to suggest trying another clinician. You could also offer to accompany them to their first appointment.

Dr. Saltz says getting a depressed person to a primary care doctor is often the first step toward recovery. "You can treat someone for depression, with medication or other means, enough that you might be able to then get them to participate in psychotherapy," she says.

If you get ‘caregiver burnout,’ don’t fade away

It can be exhausting being there for a loved one who is struggling with mental illness. That’s something that many of McLemore’s friends expressed in their interviews with Reed—that his negativity wore down on them, and that they allowed themselves to slowly drift out of his life, as a way to protect their own health.

"It’s quite tough," says Dr. Michaelis. "Especially if you’re not used to helping someone that has a significant mental illness." But, he says, if the person who’s suffering can spread it out among multiple friends, this can be good for both the person suffering and the person providing help. Also, explains Dr. Saltz, taking breaks for yourself is key to protect your own sanity and to regroup.

Depression can lead to isolation, which will make it worse

In many interviews, McLemore's friends expressed that he seemed to become more isolated and agitated by his surroundings in the last few years of his life. "In John’s case, he’s someone who was so isolated on a variety of different levels," says Dr. Michaelis. Social isolation can lead to feelings of loneliness, which also contributes to mental health issues. All of this turns into a snowball effect, making the depression harder to handle.