True Seeing + Detect Evil vs Undetectable Alignment

[Adjoint]

Does True Seeing combined with Detect Evil (or other appropriate Detect Alignment spell) allows to see through Undetectable Alignment? If not, is there any way to see through it?

[Meirril]

Well, short answer is no.

Longer answer is if you have a detection spell like Arcane Sight that would let you immediately observe that the subject is enchanted. A short time later and one successful Spellcraft check later and you'll know he has Undetectable Alignment. One targeted dispel magic later and you'll be able to get a successful reading.

On the other hand, if the subject has Mind Blank no divination spell will work on him, including spells such as Arcane Sight, True Seeings, and even Detect Invisibility. Mind Blank is a bit OP.