On an ordinary morning, in an ordinary flat, an up-till-now perfectly ordinary Bertha does an extraordinary burp. A burp so extraordinary, it knocks things over. A burp so humongously big that very soon it's causing havoc in the school canteen, the playground, not to mention her grandad's apple trees... Such a burptastic secret cannot stay quiet for long. And soon enough it lands Bertha her very own celebrity stardom...but is it all just a lot of hot air?