Many movies across different genres do their best to pull the heartstrings of their audience. In terms of documentaries, the act can be easier than usual. After all, the movies deal with real-life people in real places with real drama.

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The saddest documentaries can get real change to happen in the world. They can go as far as seeking to create new laws, seek justice for certain groups, and make otherwise lesser-known individuals famous for their struggles. Some can even be life-changing for individuals, such as making them decide to go vegan after witnessing shocking animal cruelty on the big screen. There are many documentaries out there that are sad enough to get the most stone-cold viewer emotional. When it comes to true stories, the tragedy is felt all the more.

Dear Zachary: A Letter To A Son About His Father (2008)

zachary with parents

Originally, this true crime documentary was made for the son of a man who was murdered. The goal was to show the son, Zachary, what kind of man his father was through interviews with his friends and family about him. In a rare and tragic case, the documentary actually has a twist halfway through. The baby son is killed by his mother, the same woman who killed the father.

The heart-wrenching documentary then shows how the justice system failed the family. The movie was so impactful that it inspired "Zachary's Bill" in Canada, which was signed into law to help protect children in custody disputes. Today, this movie is known as one of the best crime documentaries out there since it puts the victims at front and center rather than the murderer.

Earthlings (2005)

cows indoors

This is one of those movies that have made many of its viewers question their dietary choices. The film is about industries that make their profit from animals and treat them inhumanly. A lot of audiences claim that this is one of the most comprehensive movies of animal abuse ever made. Even for those who are not moved to tears, the content is at least disturbing to see.

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Like a lot of animal rights films, this movie has gotten some push back for its reliance on shock value. It falls into some controversy with similar films like Dominion (2018) and The Cove (2009) for graphic content and its western ethnocentric gaze on the human relationship with animals. Audiences tend to either call this movie a "must-see" or they hate it.

Blackfish (2013)

killer whale with crowd at seaworld

Blackfish was the documentary that changed how many people thought of SeaWorld. Since the movie aired, attendance to the theme park/zoo has greatly dropped. As of 2018, Blackfish still has had a major impact on SeaWorld's income. Out of animal documentaries, this one is one of the most famous. While it is not as wacky as Tiger King, audiences have often compared this movie to that docuseries.

The movie centers on the captive killer whales and orcas that live in SeaWorld. The film particularly focuses on the controversy of Tilikum, an orca that killed three people. The movie provided a ton of evidence to the animal's life of abuse that led to it aggressive lashing out.

Brother's Keeper (1992)

old man in field

True crime documentaries do not always bring an emotional edge, but Brother's Keeper did just that in the early 90s. The movie follows the true story of four brothers living in a rural community. However, one is murdered and the other is arrested for the murder. Besides focusing on the brothers, the movie also shows the stark contrast between rural life and city life. Due to the trial, media from the city suddenly came to the rural town.

The brothers all have different emotions and opinions, and the documentary makes the viewer feel like they are a part of it.

Bully (2011)

kid profile on street

This movie follows five students that suffer from bullying in their daily school life. Each student is from a different state, including Georgia, Iowa, Texas, Mississippi, and Oklahoma. The movie also explores the suicides of two students who were victims of bullying.

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The movie was made for an intended audience of the younger generation to promote anti-bullying. However, it is impactful for a viewer of any age. The biggest criticism of audiences though is that movie shows much of the problem and little of a solution.

The Act Of Killing (2012)

men in chairs with green smoke and tiger taxedermy

This twisted documentary is quite unique, as it finds former members of Indonesia's death squads and gets them to reenact their killings. However, the movie takes an unexpected turn of self-reflection from these veterans. Due to the reenacting, they remember a lot of what they suppressed from 40 years ago and the documentary becomes a disturbing and tragic emotional journey.

The movie sparked much debate in Indonesia and is an educational piece about the country's history that is worth a watch from audiences of any nation.

How To Die In Oregon (2011)

woman in hospital bed with sitting doctor

There are a surprising amount of documentaries that cover the debate of medical aid in dying (also known as assisted suicide by those against it). Another documentary that has covered the topic include The Suicide Tourist (2007). While this documentary is emotional, it is also educational. Through it, audiences can learn that Oregon was the first state to legalize a terminally ill patient being able to request medical aid to end their life.

The documentary intimately follows Oregon doctors, families, and patients who are experiencing terminal illness and their feelings about getting medical assistance to die.

Winter On Fire: Ukraine's Fight For Freedom (2015)

flower crown child in front of police in riot gear

This movie documents Ukraine in 2013 and 2014, when students formed riots and called for President Viktor F. Yanukovich to resign. Many have called the documentary a "must-see" even for those who disagree with its politics. The main complaint from viewers is that the documentary is one-sided but it does have very raw footage of the violence and scenes from the time.

Due to its graphic content of real people suffering, it can be hard not to shed a tear while watching.

Bulgaria's Abandoned Children (2007)

smiling child with backwards baseball cap

The story of this BBC documentary is coverage of orphaned children in Bulgaria and how they lack resources for medical treatments and other necessities within their institutions. Many of the children are disabled and are victims of abuse.

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The movie was filmed in Mogilino, and the documentary made many people raise money and start petitions to help the children. Actually, due to pressure from both the BBC and EU, the children's institution this film covered was shut down in 2009.

God Knows Where I Am (2016)

woman in striped shirt

This heartbreaking documentary tells the story of a homeless woman through her diary entries. The woman's name is Linda Bishop, and her body was found in an abandoned farmhouse with her diaries. Her writing tells about her struggles with starvation, God, and her own sanity.

The story is quite the tear-jerker on its own. The documentary also works hard to show how various systems that are meant to protect the homeless had failed Bishop.

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