Eva looked out of the window of the charmingly crumbling guest house and thought she might be sick. She could see Frank lying on the grass in last night's clothes - it wasn't clear whether he was conscious or not. Her husband, Shay, was in bed. She loved him, of course she did, just right now the person she most wanted to see was Connor. She didn't want to think about what had happened to Bea or how Lizzie was feeling . . .

Frank's birthday had given them an excuse for a night away. The three couples, caught between caring for the children and worrying about their parents, were ready to have a good time. The drink flowed, Dublin felt a long way away and when Frank proposed they swap partners for the night, they forgot they were stressed about their finances and exhausted by their responsibilities. In the heat of the moment, it's deliciously reckless, and makes them all feel young again. The women text the man of their choice.

One night. No obligations. No expectations. No falling in love. The only rule? No falling in love.

But life doesn't follow the rules.