Progression
The ii–V–i (minor) in Ab minor
ii–V–i (minor) in Ab minor plays Bbm7b5, Eb7 and Abm — iiø, V and i — across 3 chords. The minor-key version of jazz's core cadence: a half-diminished ii, a dominant V that borrows the raised seventh, and a minor tonic.
The chords, in order
1Bbm7b5iiø
2Eb7V
3Abmi