InspiredbywriterSunitaBalsara'sexperiencewithtinnitus,OstinatofollowsNuha,acomposerwhoseestheworldasavibrantsoundscape.SheishavingthebestandgentlestkindofmorningwhenherplayingisinterruptedbyamysteriousTone.Asshestrugglestoconfineandbanishit,theTonegrowslargerandlouder,drowningouthermusic.OnlywhenNuhastopsfightingdoesshediscoverawaytoincorporatetheToneintohermusicandlife.