On the TV screen a man walks through a darkened hospital with a firearm in his hands. He kills almost everyone he meets; several of them are armed.
When he reaches an operating theatre, he shoots the surgeon and lifts the girl on the operating table. Then he carries her away.
The scene is from the TV series The Last of Us, which has tens of millions of viewers. Surprisingly, many of us may find ourselves cheering for the killer - and it is not only because we know the story behind this scene.
"Music and sound in films and TV series can manipulate us into defending evil actions. They have an effective persuasive power," says Kristina Klungnes, a PhD candidate in musicology at the University of Oslo.
Electronic sounds can signal evil
The hospital scene is accompanied by acoustic cello music, which can evoke sadness and sympathy. This sets it in contrast to the brutality on screen.
"One consequence may be that the murderer wins our sympathy. Another may be that we begin to reflect critically, because there is a mismatch between the music and the action," says Klungnes.
Acoustic music feels familiar and intimate and is often associated with human goodness, she explains. Had viewers instead heard electronic music, the response could have been different.
"We tend to associate electronic music with monsters and the unknown. It can make a person seem less human."
Researching the soundtrack of doomsday series
In her doctoral research she studies the soundtrack of apocalyptic and post-apocalyptic science fiction series such as The Last of Us and Stranger Things.
The first depicts a world that has collapsed because people have been transformed into aggressive, zombie like creatures by a fungal infection. The other tells of families fighting monsters and forces from a parallel dimension.
Science fiction has long been a platform for themes that create fear or hope, Klungnes points out. Some series and films play on a fear of robots taking over in the future. Others deal with natural disasters and climate.
"There is a narrative out there that nature will come back and get it's revenge on us, after we have wielded our power over it for so long. This narrative is also conveyed in series and films."
Nostalgic music can create hope
In their research Klungnes and colleague Nanette Nielsen find that music is used actively to create fear, hope and other states of mind, such as compassion.
They are particularly studying music that evokes nostalgia because it is - or seems - recognisable.
In Stranger Things, 1980s music is used both to place us in time and to create hope and longing: the music becomes a contrast to all that is strange and dangerous.
Some of the music are songs by artists such as Kate Bush and The Clash. Some are also composed for the series, but with a sound palette that mimics the 1980s.
"Nostalgic music can be powerful because it interrupts the fear we experience and creates hope. In stories where the threat is ecological destruction, we believe such music can also contribute to increased engagement with climate change in everyday life," says Klungnes.
It doesn't just happen in the mind
Nanette Nielsen has worked with sound and music for many years, also connected to ethics and philosophy. From a philosophical perspective it is important to remember that when we watch a film or TV series, we are not merely passive spectators, she explains.
"We are constantly active. Music and sound can trigger thoughts, feelings and reflections. If we feel nostalgia, the experience can activate us and increase our motivation to pursue a future goal," Nielsen says.
She links this to what is called 4E cognition, a framework in cognitive science and philosophy that holds that the body and the environment are as important for thought and feeling as the brain is.
"There is a dynamic interplay between the emotional and the cognitive, and the bodily element is strong. Fear creates tension in the body; happiness brings laughter, relaxation and deep breaths. When music is used effectively, such reactions can also equip us to act."
Ask yourself which scenes you remember most
How attentive should we be to music and sound when we watch a film or TV series?
When Nielsen teaches students, she often issues a warning:
"We must not analyse the magic away. Let it work. We know the experience does not stop when the film ends."
Kristina Klungnes advice is to ask yourself which scenes you remember the most afterwards.
"Then you can go back and watch them again."
As viewers we should also be aware of the manipulative effect sound and music can have, according to the researchers.
"Music and sound are not always used in a good way. They can do harm, and if we want to preserve democracy, we need to be able to identify the power that music has over us," says Nanette Nielsen.
