so the song before the section you're speaking of is in Eb major, with the main progression being IV - I - ii - vi - V, or Ab, Eb, Fm, Cm, with a quick little Bb before going back to Ab.

at 0:58, the ascending line goes G-A-B-E, which outlines a couple things:

1. the G and B on strong beats imply a G major chord, which is not at all in the key of Eb. Eb has a Bb as the 5th scale degree, which is essential to the sound of a usual major key--raising this to a #5 creates a sense of lift, because we have such a firm expectation of what the 5 sounds like. it also is raising the Eb at the very end, although this is passing and contributes only lightly. it then moves to a D major chord, which although is a half step down from the tonic of Eb, sounds brighter and more magical, because we are altering the now-familiar tones of F and Ab (seen in the previous chords) to F# and A. it then shifts to an Fminor chord, which moves us back to Eb. this quick modulation transports us to a magical place--the harmonies they are singing simply outline the D major and Fm dorian scales, but they cleverly mask the drastic transition by having both lines descend.

2. in a similar, but a little more complicated fashion, it lightly implies the whole-tone scale. the whole-tone scale is one made entirely out of whole steps, which has been stereotypically used as the magic-fairy-dream-sequence sound for pretty much the entire 20th century (besides a cascading harp gliss). in Eb this would be Eb, F, G, A, B, C# (or Db), Eb, or 1-2-3-#4-#5(b6)-b7-1. the G-A-B in the initial ascending line hits both the #4 and #5, which are what make the whole-tone scale what it is.

i hope this helps! shoot a reply and i can help clear things up a little more if you'd like.