From the introduction:
[The player characters attempt] to recover the scroll of destruction and amulet of reversal, in order to resurrect a dead PC. The cathedral is a [actually] temple of Bardos, a minor demon from the Abyss. The priests are starting to form a small, undead army to seize control of the surrounding region. They do not want to draw attention to themselves, and are masking their activities behind the veil of a normal, good-aligned cathedral.
A brief scenario for 3rd - 5th level characters. N.B. The scenario is distributed in the rather odd Postscript format (not PDF) that must be rendered into a displayable format by an appropriate tool. It includes several maps.