Long after they had left their film careers behind them, Rotha wrote to Alwyn proposing an LP record called “Music for Documentary”. One of his suggested tracks was from World of Plenty (1943), with its score now archived, said Rotha, at the University of California. Alwyn was not opposed to re-shaping film music for the concert hall or for recordings, but the visual, musical, and sound components of World of Plenty are so interconnected that Rotha could hardly have suggested a less suitable score.

When the MoI commissioned Rotha for this survey of “the problems of world food, its production, its distribution, and its eating”3 he had eight other titles in production. Since, however, he could not turn down a major contract, he experimented and cut corners. He collaborated with Eric Knight - the title was suggested by Alwyn himself - on a script that illustrated its thesis through a discussion between the voice-overs of a narrator and questioning sceptics. All the visuals were rummaged together from film libraries, apart from the graphics and interviews. Like many of Rotha's titles, the result is instructional film as entertainment, brims with innovation and imagination, and balances music and sound-effects equally with the pictures. Alwyn's composition is mainly instrumental punctuation, enlivening the pictures with a type of simple mickey-mousing. In the first graphics sequence, for example, each item in a list of foods is musically ticked off in turn by a plucked d’ string : “Cereal (d’), vegetables (d’), wheat and dairy produce (d’),” and so on. More graphics sequences follow, which Alwyn tickles with rising and falling glissandi, xylophones, drum rolls, drum beats, a vibrating cymbal, and other fancies, including at one point a backwards drum roll.

There are few even moderately long music cues. Early on a march enlivens a succession of worldwide farming and factory processing shots ; but after an initially stirring timpani beat, the score becomes relatively bland, perhaps to avoid distracting from the argument. These filmmakers knew what they were about, and it is interesting to contrast this march with another depicting the effort against the threat of the swastika (which, to harp glissando, zooms alarmingly out of the sky, Rotha-style). Here, all is determination. A sharp, energetic, articulation of ostinato marching strings gradually climbs the scale, counterpointed with terse and aggressive outbursts on higher chords and interspersed by trumpet fanfares.