|First appearance||"Love's Labours Lost in Space" (1ACV04)|
|Voiced by||Billy West|
M5438 is an entity of pure energy. He was introduced by Amy to Leela who was looking for a date at The Hip Joint. However she turned him down. Bender believes him to be gay and from "a dimension that's big on musical theatre." Despite this, Amy later decides to leave with him.
No electronic effects were needed to produce the voice of M5438 - according to the audio commentary for The Beast with a Billion Backs, West uses his chest voice to create the high-pitched electronic voice, which was initially thought to be a problem with the sound equipment in the recording studio.
The name "M5438" probably comes from the names of the Messier objects, which are galaxies, nebulae and star clusters with names like M42 and M31, up to M110.
M5438: I understand. One day you will evolve beyond your physical body and on that day, I hope you will pick up the phone.