Zoe and Ava have been best friends for ever. So have Lottie and Isabel. All four of them together make the perfect group. Zoe thinks life is just as it's meant to be - until an extra chair appears in the year three classroom.
Now Ava is having playdates with the new girl. And Isabel is making friendship bracelets for someone other than Lottie. Suddenly everything feels wrong. Are the best friends forever going to become best friends for never?