The first song on Boingo's self-titled album (released in 1994). The album was incredibly different from the albums released by the band as Oingo Boingo, as the opening song makes quite clear. Far from Oingo Boingo's 80s danceable rock and typical pop song length, "Insanity" mixes a somewhat standard rock band set up (guitars, bass, drums, etc.) with an orchestra to give the song a very moving and dramatic feel. The song also features some interesting percussion, with Danny Elfman (singer/songwriter/other things that are usually rhythm guitar) banging away on a huge bongo-ish drum (footage of this can be found on the Farewell videos). "Insanity" clocks in at seven minutes and fifty seven seconds in length, almost twice as long as what most radio stations typically edit longer songs too.
The words to "Insanity" are a satirical stab at Christian values of purity (or rather how many Christians act about them), racism in society, and obsession - much darker than Oingo Boingo's material, though with the Oingo quite a few songs still had a theme of pointing out flaws in society and obsession (but then, quite a few didn't as well). The music reflects this in this song (and the album as a whole) a lot more than previous Oingo Boingo material. Danny Elfman's work on film scores undoubtedly has a lot of influence here. (Think of any Tim Burton flick aside from Ed Wood and, as of this writing, the score will have been composed by Elfman. Not to say he hasn't done anything unrelated to Burton.)
As usual, the words and music were both written by Danny Elfman. The song was produced by Elfman, Steve Bartek, and John Avila. Aside from the basic band and orchestra setup used throughout the album (see Boingo for specifics) the liner notes credit Cameron and Taylor Graves for background vocals and the following Boingo member relatives as their Insanity Gang: Mali Elfman, Liela and Jennifer Avila, and Juanita Tiff.