Nick Sullivan - Olivia McPherson

Olivia "Mac" McPherson, played by Silvia de Crespigny, made her first on-screen appearance on 3 June 2004. Olivia is a police officer who dates both Jack Scully and Stuart Parker.

de Crespigny Said she jumped at the chance to play the "mysterious" Olivia. The role was her first television job and she said that it was "brilliant" and that the cast had been very welcoming towards her. de Crespigny described Olivia as a "feisty young lady" and said "She's a party girl, but she has a life that she likes to keep split. She likes to shake things up a little bit." de Crespigny added that she is not similar to her character and clubbing is not her forte, but she does enjoy going out and having fun.

Olivia is the third generation of her family, after her father and grandfather, to become a police officer. She eventually becomes a senior constable, but she starts going out clubbing every night and taking drugs. Olivia becomes corrupt and helps rob building sites in order to fund her nights out. She meets Jack Scully (Jay Bunyan) at a club and they start spending a lot of time together. She makes sure that he only knows her by her nickname, Mac, and they eventually start dating. Olivia and Jack are involved in a small car crash on their way home from a night out. When the police arrive, Olivia tells Jack to leave as the police officers would probably recognise her. Olivia is partnered with Stuart Parker (Blair McDonough) and Stuart develops a crush on her. When he makes a mistake in his log book, Olivia covers for him. Stuart becomes suspicious of Olivia when he sees her taking something from a known criminal. Jack turns to Olivia when the site he is working on is robbed. She lends him some money and tells him that there is no hurry to pay it back. However, she suddenly demands the money back from Jack and almost runs over Summer Hoyland (Marisa Siketa). Olivia goes back to her ways and starts taking drugs again. Jack refuses to go to a club with her and she turns nasty. When Olivia is unable to get her hands on any money, she suggests to Jack that they stage a robbery at his site. When Stuart questions Jack, Olivia's cover is blown and Jack is shocked to find out that she is policeman. Olivia discovers that Darren Stark (Todd MacDonald) has a criminal record and decides to pin the robbery on him, but Darren has a strong alibi. Olivia and Stuart attend a Police Ball together and when Jack loses control of his car while on the phone to her, she ends their relationship. Olivia decides to turn over a new leaf and she and Stuart sleep together. She then tells him everything and he decides to report her for her actions. Olivia says goodbye to Jack and tells Stuart that he will make a great police officer.

The BBC said Olivia's most notable moment was "Being revealed as Stuart's partner in the Police as well as Jack's mystery woman."