The final episode of the Australian crime drama, which starred Chelsie Preston Crayford and Danielle Cormack as two of Sydney's biggest vice queens from the 1920s, aired last night to an audience of 1.449 million viewers.
According to AAP, Underbelly: Razor was the most watched programme of the night, followed by current affairs show 60 Minutes with 1.414 million viewers, David Attenborough documentary Frozen Planet with 1.282 million viewers and then Sunday Night with 1.207 million.
Channel Ten's highest rating show for Sunday was Junior MasterChef, while ABC made it into the top ten list with UK drama Merlin.
The fourth series of Underbelly rated consistently well throughout the series, despite new Daniel MacPherson drama Wild Boys beating it in the ratings when it first premiered.
It also went head-to-head successfully with Stephen Spielberg's new thriller series Terra Nova.
When Underbelly: Razor first aired, child psychologists labelled it as too "explicit' for television.
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