The main theme of "Children of the Stones" is written on the acoustic scale, ambiguously fluctuating between a tonality of C and D major. A signature two-chord harmonic progression, Em9 to G/C, is heard throughout the seven-part series at key dramatic points. A secondary theme is treated in canon and is diegetic music, representing a hymn sung by the spellbound villagers in the story. This theme is later echoed in the guitar and bass when the main child protagonist, Matt, uses his latent psychometric abilities. The secondary theme also concludes the series in a light jazz arrangement, establishing a lighter tone before the final twist is revealed.