It’s a familiar scenario. The protagonist can’t sleep. He or she can’t focus and their head is full of chaotic memories and emotions. When they’re finally able to doze off, they are jolted awake by a disturbing nightmare. It’s the same nightmare the protagonist always has: a flashback from the past. Something terrible happened, which they have never come to terms with. The protagonist has repressed his or her memories of the experience, repressed his or her guilty feelings, and repressed his or her anger. Now he or she must face reality. Although the protagonist can never change the past, he or she will never rest until the dilemma is resolved. The protagonist can achieve this this by fighting for the truth, admitting their failings, or by carrying out an act of redemption. Only after one of these resolutions will they be able to sleep.
The character’s trauma, inflicted by them, or on them, stops them from living, and stops them from sleeping. They are stuck in a purgatory of sleeplessness. This is a typical insomnia scenario in storytelling.
There are many variations on this trope. Sometimes the protagonist is afraid of falling asleep because something horrific might happen to them: nightmares, monsters lurking in the dark, a person or creature invading their dreams. The protagonist suffers from increasing exhaustion, which can only be resolved when he or she is able to face the truth, or to fight for the truth, and to come to terms with their trauma.
Insomnia can also be used to heighten the protagonist’s challenge, along with other afflictions like: smoking, drugs, and alcohol. It’s a tension heightening device that creates another hindrance the protagonist must overcome.
Sometimes insomnia can become the catalyst in the story. The central characters might meet one another because they have insomnia. This happens in Lost in Translation. In Before Sunrise the two main characters are waiting for the morning train and kill time walking about the streets of Paris. Although it’s not technically insomnia, they cannot sleep because they do not have a hotel room. In Cashback the protagonist’s insomnia is the catalyst for him taking a nightshift at a supermarket and meeting new people.
Insomnia can signify to the audience that the protagonist is experiencing a psychological dilemma or horror. In Vanilla Sky the central character loses his identity, which is visually expressed through his need to wear a mask. He is unable to sleep because he has lost touch with who he is. In Invasion of the Body Snatchers characters fear sleep because the alien entity clones people in their sleep. And in Nightmare on Elm Street characters are afraid of sleep because Freddy Kruger will take over their dreams and torment them to death. In The Haunting ‘Nell’s’ sleeplessness and anxiety becomes amplified within the house, driving her insane.
The emaciated protagonist in The Machinist suffers from insomnia, delusion and paranoia. Once he realises that he is the problem, his only path is an act of redemption. Insomnia is probably the best example of the ‘insomnia story’. Will Dormer (his name is a pun on sleep) suffers from insomnia, and his flashbacks relate to a traumatic incident in his past. He will find rest through self-revelation, coming to terms with his memories, and acting to rectify his wrongdoing. Sleep comes after the truth is exposed, after an act of redemption. Sleep is the final reward.