We follow the main protagonist, Nia, as she decides to go for one last adventure before 'settling down', travelling - along with four other scientists - to the Arctic island of Safísk to conduct research. As the crew learns about a rare bird that lives there - and changes the landscape of its habitat in the process - the island revolts and decides to get rid of the would-be occupiers.

Dilynir hynt y prif gymeriad, Nia, wrth iddi benderfynu mynd am un antur olaf cyn 'setlo i lawr', gan deithio - ynghyd â phedwar gwyddonydd arall - i Ynys Safísk yn yr Arctig i wneud gwaith ymchwil. Wrth i'r criw ddysgu am aderyn prin sy'n trigo yno - a newid tirlun ei gynefin yn y broses - mae'r ynys yn gwylltio, ac yn penderfynu cael gwared ar y bobl sy'n trio ei meddiannu.