You Guys are KILLING me.
The Krell were a mythical race in the '50s SciFi classic
'Forbidden Planet'.
Just my opin, but one of the most literate / intelligent well paced SciFi flicks ever.
A great cast including a very young Ann Francis among many others, including Leslie Nielsen in an early, serious role.
And, from the Audiophile standpoint an incredibly interesting soundtrack with all Theramin music/effects. (pre MOOG by several decades) Must hear on good system, but you already knew THAT.