'It's the eve of Hector's 40th birthday and his wife Aisha has organised a barbecue with their friends and family. Hector is ambivalent about celebrating the milestone and longs for the carefree days of his youth. He loves his wife, but her controlling nature and singular focus on the party only serve to heighten these feelings. Nonetheless, Hector is a genial host. The party begins, and tensions arise almost immediately between Hector's mother Koula and Aisha. Koula has catered, despite Aisha's protestations, and she and Manolis have bought Hector a birthday present - a family trip to Greece - which clashes with Aisha and Hector's planned trip to Bali. When Hector refuses to confront his parents about it, Aisha is infuriated by what she sees as his loyalty to family over her. Hector escapes by taking drugs and flirting with 17-year-old Connie, the teenager he's having an affair with.
'As the day progresses and guests arrive, frictions between the adults and children emerge. Hugo, the four- year-old son of Rosie and Gary, persistently creates havoc amongst the other kids, picking fights, breaking other kids' games, and refusing to play by the rules. However rather than disciplining him, Rosie dotes on him, refusing to acknowledge his problematic behaviour. There are clear familial and social divisions within the group, and differences in race, culture, wealth, and morality, shape the way people interact. When another fight amongst the kids breaks out, Hector tries to remedy it with a game of backyard cricket. But things quickly turn ugly when Hugo throws a tantrum after Hector's nephew Rocco, bowls him out. Swinging the cricket bat in fury, Hugo refuses to sit out of the game. When Harry spies this and fears that his son Rocco might be in danger, he slaps Hugo. Rosie and Gary are outraged. This event and what follows divides the group as each person at the barbecue is forced to take a side.'
Source: ABC website, http://www.abc.net.au/tv/theslap/