D2: Shrine of the Kuo-Toa (1978) - UK printing

From the web:

Dungeon Module D2 is the second of three modules in the D series. It can be played alone or in conjunction with G series modules and the Q1 module. I contains both a player and dungeon master version of the temple complex. It also introduces 2 new monsters for use in the module and or AD&D in general.

In Shrine of the Kuo-Toa, the PCs enter and pass through a religious shrine to Blibdoolpoolp, the sea mother goddess, on their way through the Underdark.