S4·E10 Blue

U is upside-down, next to an upside-down tree, and the whole of Alphaland is blue. How did that happen? This episode introduces the long U sounds, the digraphs '-ew-', '-ue-' and '-u-e-' and the words "new", "grew", "blew", "flew", "true", "blue", "glue", "rescue", "tune", "lute", "flute", "prune" and "mule".