[Bars 1-9] The intro targets the b7 (G) from A7 (bar 2) to nail the changes between A7 and C#m. This note is also the b5 from the C# Blues Scale (C# E F# G G# B), so covers some well-trodden Blues-Scale vocabulary. Of particular note are bars 8-9, which eventually target the V chord with a classic Gary turnaround lick. [Bars 10-17] The verse section follows tried-and-tested blues-style ‘call and answer’ phrasing, in between the vocal lines. The rhythm guitar actually plays C#m chords throughout this section despite the more explicit I- IV (C#m – F#9) that is implied in the notation and by the bass movement.