Matthew的父母希望他將來當個醫生改善家裡的生活，但Matthew卻不知到自己想做什麼，直到有一天有機會參觀博物館，各類型的畫作讓他大開眼界，周遊在豐富色彩的畫作間，彷彿置身於夢境之中。遠遠看見一位美麗女士Nicoletta，Matthew深深被吸引。當天晚上做了個夢，自己與Nicoletta散步在色彩之中，好幸福……。雖然夢想發下自己仍處於家中破舊的角落，但恍然間，Matthew明白自己將來要成為一位畫家，而夢想果真實現！藝術能改變我們的世界，努力能讓夢想實現，這個故事是最好的寫照。
A cleverly told and beautifully illustrated tale of self-discovery from four-time Caldecott Honor winner Leo Lionni.
Matthew the mouse lives in a dreary corner of a dusty attic. But a trip to the museum helps him to see his surroundings in a new way. With brush in paw, Matthew sets out to paint "the shapes and colors of joy."

Leo Lionni, an internationally known designer, illustrator, and graphic artist, was born in Holland and lived in Italy until he came to the United States in 1939. He was the recipient of the 1984 American Institute of Graphic Arts Gold Medal and was honored posthumously in 2007 with the Society of Illustrators’ Lifetime Achievement Award. His picture books are distinguished by their enduring moral themes, graphic simplicity and brilliant use of collage, and include four Caldecott Honor Books: Inch by Inch, Frederick, Swimmy, and Alexander and the Wind-Up Mouse. Hailed as ＂a master of the simple fable＂ by the Chicago Tribune, he died in 1999 at the age of 89.