A picture book adventure about a scruffy dog who helps Princess Victoria escape Kensington Palace and enjoy a day of fun that she'll never forget. Rex lives at the Tower of London and likes nothing better than sniffing around in juicy litter bins. But his favourite bin of all isn't just a litter bin - it's also a time machine. He jumps in and he's transported back to Kensington Palace, home to Princess Victoria. She's stuck inside doing her lessons - but Rex helps her escape for one brilliant day out in 19th century London.