Derek Dietl
General information







Susan Murphy (ex-fiancé)
Mrs. Dietl (mother)

Behind the scenes
Voiced by

Paul Rudd
Nolan North


Gaston from Beauty and the Beast

Feature film

Monsters vs. Aliens


Derek Dietl is the secondary antagonist in Monsters vs Aliens. He is Susan's ex-fiancé who works as a weatherman for the local news station in Modesto, California. Ambitious, opportunistic, and selfish, he jumps at every opportunity to enhance his career whenever one presents itself, causing him to place his job before anything else, including his relationship with Susan. When Susan becomes Ginormica, Derek breaks up with her because he does not wish to be married to someone who could overshadow his career. At the end of the film, Susan gets her revenge by publicly humiliating him.

Derek reappears in "It Came from Channel 5" trying to get into Area Fifty-Something to prove that they are hiding aliens. Coverton tries to get in touch with him to cause a panic, and tricks B.O.B. into helping him. When Derek runs into Susan he's delighted that she's now able to control her size, but is rejected by Susan. He's eventually mind wiped by Sqweep to keep him from revealing the aliens.

Derek Dietl is voiced by Paul Rudd in the film and Nolan North in the series.


Derek Dietl was a selfish jerk when he told Susan they are not going to Paris. He says they're going to Fresno, so he can have the job interview. He said he wasn't looking to get married and spend the rest of his life in someone else's shadow, which hurts Susan really awfully bad. In general he will use anyone to help forward his career.


  • Derek Dietl has no crooked thumbs, unlike his mother which made him skip a generation.
  • Derek Dietl is similar to Gaston, the antagonist from Beauty and The Beast, who likes to boast how he will marry Belle, but he really is a jerk.
  • Derek and Gallaxhar were the two villains of the film to be defeated.
  • Derek is the third human character to appear in the series behind General Monger and President Hathaway. Susan doesn't count as she's classified as a monster.