Episode 424: The Story of Mister Z and Mister X

== Plot ==
Mister Z lets Mister X have his sound (the same sound that starts "Zipping Zippers"), so Mister X can finally start words like xylophone, xerus and xenops. It can even be a Christmas episode, where Mister Z wants to give Mister X something special.
== Trivia ==
* Mister X becomes the first Letter Person to have two sounds.
Category:Letter People episodes