"Hammerhead" is the second single from Australian rock musician James Reyne’s debut self titled solo studio album in (1987). The track featured uncredited backing vocals by Olivia Newton-John.

Reyne reflected on the song saying; ""Hammerhead" was not necessarily about me, but let’s say I thought I knew what I was talking about. I wrote it with Simon Hussey; the music Simon and I wrote together and I wrote the lyrics. From memory it seemed to come quite easily. I shouldn’t make too much about the fact that it’s about drugs. It can be taken many ways. It was an exercise in trying to write a song about that subject but to also make it that it could be about a relationship. It’s a song about a relationship. And whether that relationship is with a substance or a person, it’s an obsessive relationship".

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