Away is set in Australia in the late 1960s, and it opens just after a school performance of A Midsummer Night's Dream. We are introduced to two actors in the play, Tom and Meg, and each of their families. Tom's parents are Harry and Vic, two immigrants from England who work in a factory. Meg's parents, on the other hand, are Gwen and Jim, two wealthier Australians. Notably, Gwen is very snobby and easy to anger, and she often snaps at Jim and Meg. Tom and Meg share a degree of romantic interest, but Gwen refuses to let them see each other because she thinks of Vic and Harry as below her. As the play begins, we are also introduced to Roy and Coral, the school's headmaster and his wife. Their marriage has suffered greatly after the death of their son in the Vietnam War, and Coral has been acting vacant and despondent in the time since. The families discuss their plans for the upcoming holiday vacation and part ways. Later, Coral meditates to herself about the preciousness of youth and the terrible ease with which it can be taken.
As preparations are being made within each family for the holiday, Harry tells his son that he ought to act like he is enjoying himself for his mother's sake, even if he truly isn't having a decent time. He alludes to past trouble and Tom's time in a hospital. Meanwhile, Gwen yells at Jim and Meg, and Jim tells Meg that Gwen's overeager planning and overzealous snobbery are the result of her previous poverty and a desire to never return to such conditions. Roy tries to subdue Coral in their home by telling her that the loss of their son was necessary to preserve Australia's high standard of living, but he also sharply rebukes her for her behavior and tells her that he cannot keep giving her leeway to act as she does. Back at Vic and Harry's home, Vic notably also tells Tom to act happy for his father's sake, reversing the same advice given by Harry to his son.
On their actual vacations, the challenges faced by the families grow. At a fancy hotel, Coral falls in with a young man named Rick, who is at the hotel for his honeymoon. Eventually, Coral and he begin a brief fling, and when Roy discovers it, he threatens Coral with electroshock therapy and institutionalization. Meanwhile, at a campsite, Gwen and Jim have a huge fight over gifts that Jim has apparently left at home by mistake. Afterwards, Jim once again tells Meg about Gwen's past and the desire to be free and independent from that past that leads her to act as she does. Suddenly, a large storm tears through the campsite, and Meg, Gwen, and Jim are forced to save what they can and flee. Tom's family, on the other hand, misses the storm and quietly enjoys both their vacation and their gifts on a secluded beach.
Eventually, however, Meg, Gwen, and Jim show up at Tom's beach by chance. Meg saw the sign from the road and insisted, against her mother's wishes, that they briefly stop there. At the same time, Coral has shown up at the beach after running away from Roy on New Year's. Later, Gwen spends alone time with Vic and Jim with Harry, during which each of Tom's parents tells each of Meg's parents that Tom has terminal leukemia. They wanted to hide the fact from him and allow him to enjoy one last vacation, so they do not act sad in front of him. We also understand at this point that this is why each parent urged Tom to feign enjoyment for the other's sake. This knowledge shocks Gwen and Jim into reconciliation and new appreciation for each other. Meanwhile, Tom and Meg are sitting together on the beach. Tom tries to pressure Meg into sex, but she refuses, which leads him to tell her about his illness. Meg grows distant, and Coral and Tom grow close and plan a play together. The play is a testament to resilience and authenticity in the face of pressure. After the play, Vic and Harry exit, not to be seen again.
The play closes with the remaining two couples coming together with a newfound understanding of how precious intimacy is. This then blends directly into another school performance, this time of King Lear, during which the drama teacher summarized many of the themes of both Lear and Away. Depending on the version, either Tom or another actor (implying Tom's death) then concludes the play by reading lines from King Lear about the way that old age and death make way for youth and inheritance.
