Melanie Jayne Lynskey was born in New Plymouth, New Zealand, to Kay and Tim Lynskey. Growing up in a close-knit family, her early life provided a strong foundation for her future endeavors. Her upbringing in New Zealand instilled in her a down-to-earth personality, a trait often remarked upon by both fans and colleagues, and which perhaps helped her to avoid many pitfalls of fame.

At the age of 16, Lynskey landed her first professional acting role as Pauline Parker in Peter Jackson's critically acclaimed psychological drama 'Heavenly Creatures.' This marked a significant breakthrough for the young actress, showcasing her remarkable talent and establishing her as a rising star on the international stage. The film, based on a true story, also starred Kate Winslet and received widespread recognition, including an Academy Award nomination for Best Original Screenplay, setting the stage for Lynskey's burgeoning career.