A terrible book at that. I had to study it for my GCSEs I know why they came up with the name though.
#spoilers
Boring story short, it’s about these 2 migrant workers (George and Lennie) in America during the great depression. They go from ranch to ranch with a dream (to own their own ranch and house and what not) but Lennie has the mind of a child (and the strength of the hulk) for some reason and he’s always getting the two into trouble in the final ranch that they come to he accidentally kills the wife of the owner’s son and George in the end gives up and kills Lennie. Thus never achieving the American dream.
The name of the band stems from that as apparently the founding members had other plans for life that didn’t go as they should apparently.