‘Pilots of the purple twilight, dropping down with costly bales’ is a line in Alfred Tennyson’s poem Locksley Hall (written 1835).
Meanwhile, obsessed scientist Plummer is nearing a nervous breakdown, trying to complete a magnetic disintegrator that will convert matter into pure energy.
Due to the interference of Plummer's girlfriend, Janet Lane, Ikar is unable to control or understand his adopted emotions.
The alien has great difficulty in understanding such things as love and beauty - concepts utterly foreign in his world.
Meanwhile, Plummer uses Ikar's data to harness a fantastic energy source and fashions a weapon capable of destroying all life.