When everything seems to be going wrong, sometimes you just have to stand up for what you believe in, even if it's just in your own little corner of the world ... This was meant to be Alice's year to shine, but things are already going wrong... At school, she's given young environmental activist Greta Thunberg as her pen pal for a fictional writing assignment. Why couldn't Alice get someone easy to write to, like a pop star? Then she's put in charge of taking the Harmony Day Food Fair online, which seems impossible, especially when she is teamed up with the most annoying boy in her school. As if she didn't have enough on her plate, Alice gets kicked out of her bedroom by her grandmother coming to stay. And no matter what Alice does, she'll never be able to live up to her infuriating big sister's achievements, right? Through her letters to Greta, Alice finds herself opening up about her life. And as Alice approaches the hard questions by wondering, 'What would Greta do?', she starts to believe that she can make a difference - a big one.