Tim Williams has a happy marriage, a good relationship with his teenage son Max and the respect of his peers. Everything about his working and personal future is looking quite bright. The problem though: 15 years ago, Tim had a brief affair with the drug-loving Nat Manning. The affair ended in Nat finding out she was pregnant. After admitting this to his wife Christine, they patched up their marriage and fought hard for custody of the child. Nat moved to London and has hardly been heard from since. But now, 10 years later, Nat is back in their lives. This time for good.

Gabriel returns to Melbourne and stays with Vince and Ally. His attraction to Ally is noticed by everyone but her. When Max discovers the body of a man, it becomes a secret that is kept between the teenagers. Romeo then takes it on himself to try and break into the dead man's house.

Vince asks his mistress Em to go on a skiing trip, which shocks Gabriel, who is going along as well. When Em is injured and they have to go back to Melbourne, Vince begs Gabriel to pretend she is his girlfriend so that Ally doesn't become suspicious.

When the police arrive at the dead man's house, where the teenagers are having a party, Max calls Nat so that he doesn't get his father Tim involved in the situation. However, this only makes Christine feel more insecure. Vince finally manages to convince Ally that Em is Gabriel's girlfriend.

When Tim is offered the job of health minister, he has a tough decision to make as he will only get the job if he gets rid of his mentor, Pat. Meanwhile, Romeo wins over Charlotte's heart, much to Max's disappointment.

When Ally tells Vince she kissed someone while out on the town with Nat, Vince becomes extremely jealous. Meanwhile Tim starts to question how much his career means to him when he sees how much he has hurt his mentor.

Still affected by the crisis at his work, Tim goes out on a flirtatious, alcohol-fuelled night with Nat, which devastates Christine. Meanwhile, Gigi tells her mum that Em is not actually Gabriel's girlfriend. When Ally questions him about it, he admits his true feelings for her.

Confronted with a hospital crisis, Gabriel contacts Tim, who plays political hardball to secure more emergency funding. Ally is devastated when she uncovers Em and Vince’s affair. She exposes Vince and takes refuge in a hotel with Nat. Now Max’s girlfriend, Charlotte moves in with Tim and Christine.

Tim finds out through Em that Vince's shady dealings will compromise him politically and could destroy his career. With his marriage on the line, Vince struggles to manage his family, ignoring Tim's desire for confrontation. Nat finally elicits Tim's confession that he’s still attracted to her. As the tension mounts between Max, Charlotte and Romeo, all the teenagers are involved in a car accident.

When the press seizes on Max's involvement in the car accident, Tim finds himself facing a political minefield.

Nat pushes Ally to leave Vince permanently. When Gabriel declares his intentions to win Ally, Vince is galvanized into action. In the wake of the accident, all of Christine's mounting anger is unleashed.

As pressure builds, the landscape is irrevocably transformed by an unexpected turn of events.