For Guy Leschziner's patients, there is no rest for the weary in mind and body. Insomnia, narcolepsy, night terrors, apnoea and sleepwalking are just a sample of the conditions afflicting sufferers who cannot sleep – and their experiences in trying to are the stuff of nightmares. Demonaic hallucinations frighten people into paralysis. Restless legs rock both the sleepless and their sleeping partners with unpredictable and uncontrollable kicking. Out-of-sync circadian rhythms confuse the natural body clock's days and nights.

Then there are the extreme cases. A woman in a state of deep sleep who gets dressed, unlocks her car and drives for several miles before returning to bed. The man who has spent decades cleaning out kitchens while 'sleep-eating'. The teenager prone to the serious, yet unfortunately nicknamed, Sleeping Beauty Syndrome, stuck in a cycle of excessive unconsciousness, binge eating and uncharacteristic displays of aggression and hypersexuality while awake.

With compassionate stories of his patients and their conditions, Leschziner illustrates the neuroscience behind our sleeping minds, revealing the many biological and psychological factors necessary in getting the rest that will not only maintain our physical and mental health, but also improve our cognitive abilities and overall happiness.