Forest 404 was a science fiction podcast produced by the BBC that starred Pearl Mackie. The series debuted in 2019 on BBC Sounds and was later broadcast on BBC Radio 4. The 27-part show was composed of nine narrative episodes, each accompanied by a soundscape and a discussion on the show's themes. The story was written by Timothy X Atak, and the theme music was by Bonobo.

The narrative of the show follows a data analyst named Pan who lives in a dystopian 24th century. Pan is tasked with cataloguing and deleting the remaining audio from before a global catastrophe. While reviewing the audio, she discovers recordings of the natural world and finds that they have a profound effect on whoever listens to them. The show received largely positive reviews and, in 2020, won both a WGGB award and an ARIAS award.

The podcast was accompanied by an academic study led by Alex Smalley with funding from the Arts and Humanities Research Council. The study focused on the psychological effects of listening to sounds from nature. The project was a collaboration among The Virtual Nature Project, BBC Radio 4, the BBC Natural History Unit, the University of Bristol, the University of Exeter, and the Open University.

The show is an environmental thriller and dystopian science fiction podcast commissioned by Rhian Roberts and written by Timothy X Atack. The show was produced and directed by Becky Ripley with sound design by Graham Wild and theme music by Bonobo.^[1][2] The 27-part series is composed of nine narrative episodes, each accompanied by a soundscape and a discussion on the themes. The soundscapes are approximately five minutes in length and utilize binaural recording to immerse the listener in the sounds of the natural world similar to forest bathing. The show was first released as a podcast on BBC Sounds and later broadcast on BBC Radio 4, and was also made available as a box set.^[3][4]

Timothy X Atack credited works such as The Left Hand Of Darkness and The Word for World Is Forest by Ursula K. Le Guin as influences on the story of Forest 404. Atack cites his experiences working in the BBC Archives of natural history sounds, and specifically a Digital Audio Tape of a Sumatran rainforest recorded by Sue Western, as an inspiration for the show's premise. The inspiration to use "forest" in the title came from Rhian Roberts's childhood stomping grounds, and the full title is a reference to the 404 Not Found error—the protagonist is literally searching for the forest and is unable to find it.^[5][6]

The show featured an all-female cast starring Pearl Mackie. The show was created in Bristol where Mackie had previously attended the Bristol Old Vic Theatre School. The characters included LGBT people and people of color, which is uncommon in media related to climate change.^[4][7]

• Pearl Mackie as Pan
• Tanya Moodie as Daria
• Pippa Haywood as Theia

In the 24th century during an era called The Fast Times, people live off-world or in crowded skyscrapers high above the Earth. After a catastrophe referred to as The Catacylsm, the majority of the world's digital information was lost and nature was destroyed. Any remaining data from before The Cataclysm is untethered from its historical context and takes up valuable space needed for the city to grow. Pan, a sound archivist working in the "heavy data" section at the Department of Convocation is tasked with cataloguing or deleting the remaining audio files from The Slow Times and she is good at her job—clearing 40 to 50 terabytes a week.^[8][9][10]

While working through the audio archives, Pan discovers a recording of a rainforest and, having never even seen a tree, is unfamiliar with the sound. Fascinated by what she believes is disjointed music, Pan begins to investigate and finds more perplexing audio files. Her boss and potential love interest, Daria, learns about her new obsession, and informs The Hands at the Department of Convocation. These automaton-like police exist to serve the "Law of Progress" and refer to the audio that Pan has uncovered as The Rupture, which has the potential to spread a deadly virus throughout the city. While the audio has a strange effect on her, Pan seems to be immune to the virus.^[11][12]

Daria and The Hands pursue Pan and she flees to the lower city known as Fumetown. The pursuit and Pan's investigation lead her further downward where she encounters Theia, who is the last living human. Theia is protecting an enormous underground tree and reveals that the audio clips are of nature. What the Department of Convocation calls The Rupture is nature and the deadly virus is the unbearable realization that humans were responsible for its destruction. When listening to the audio, this realization is so overwhelming it can be fatal. The story concludes with Pan travelling toward a radio tower to broadcast the audio file titled "Forest 404" and share the knowledge of nature and its loss with the world.^[6][12]

The plot and writing of the show received mixed reviews from critics. Writing in The Observer, Sean O'Hagan asserted that the show was "conceptually bumpy" and contained some "jarring moments" and plot contrivances that broke his suspension of disbelief.^[8] In contrast, Torri Yearwood recommended the show in The Tech, describing the story as "beautifully believable" and praising the series for its world-building and character development.^[9] Commenting in Refinery29, Jazmin Kopotsha wrote that the show has a captivating story that draws listeners into the series, but more strongly emphasized the compelling protagonist as the driving force that keeps the listener engaged.^[11]

The show's experimental format and companion episodes received overwhelmingly positive responses from critics. Sam Fritz at the Mississippi Valley Conservancy remarked that the companion episodes allowed the show to "transcend other mediums" and provide context for the plot while grounding the narrative in reality.^[4] Recommending the show on the Australian Broadcasting Corporation, Carl Smith praised the show for its experimentation with form and for pushing the boundaries of podcasting.^[13] In the South China Morning Post, Suji Owen argued that the show's use of companion episodes deepened the themes and ideas throughout the series.^[14]

The show's sound design received positive responses from reviewers. Praising the show's use of binaural technology, Sarah Hemming expressed in the Financial Times that she felt the "richly textured soundscape" was best appreciated with headphones.^[3] Similarly, Barry Didcock of the The Herald recommended listening with high quality speakers and emphasized that he enjoyed the show's sound design.^[10] Writing on the website Stuff, Katy Atkin recommended the show, calling it "a masterpiece in sound design" and asserted that it intensified the story.^[15]

The Forest 404 Experiment was an academic study that accompanied the podcast as a collaboration between The Virtual Nature Project, the BBC Natural History Unit, BBC Radio 4, Exeter University, Bristol University and the Open University. The experiment was open to participation from 4 April 2019 until 31 October 2019, concluding with a total of 7,596 participants. The podcast encouraged listeners to take part in the study, which examined how the sounds of nature impact health. While many previous studies have focused on the general effects of nature on health, there is limited data on the specific effects of hearing nature.^[22][23][24]

The experiment was conducted on an online platform called nQuire, which was developed by Open University and the BBC. The platform was intended to provide a space for anyone to design and conduct academic studies and to facilitate mass participation in experiments. The nQuire platform was formally launched with The Forest 404 Experiment. The study was funded by the Arts and Humanities Research Council and was conducted by a team from the University of Exeter and the University of Bristol, which was led by Alex Smalley. Participants answered a series of randomized questions in response to nature sounds and poetry about nature. Many of the sounds were from the BBC natural history archives and the poetry was read by Pippa Haywood.^[25]

The results of the study were published in the journal of Global Environmental Change in May 2022. When participants listened to landscape sounds such as waves or rain they experienced therapeutic effects. If the recording included wildlife noises such as birdsong the listener was even more likely to experience relief. Similarly, whenever the audio triggered the participants' memories there was an even greater positive effect and an increased desire to preserve or protect the soundscape. If the audio did not contain wildlife sounds, the motivation to protect the soundscape decreased, which indicates that a decline in the quality of the environmental noise also led to less conservationist behaviors.^[24]

• List of science fiction podcasts
• List of environmental podcasts

• Official website
• Forest 404 at the Internet Archive
• Forest 404 at The Virtual Nature Project