The Halfling's Gem

Description for THE HALFLING'S GEM by R A Salvatore:

Assassin Artemis Entreri whisks his kidnapped victim, Regis the halfling, south to Calimport and into Pasha Pook's vengeful hands. If Pook can control the magical panther Guenhwvvar, Regis will die in a real game of cat and mouse.

Using an enchanted mask, dark elf Drizzt Do'Urden hides his heritage and races with the barbarian Wulfgar to save their light-fingered friend. An unexpected ally arrives just as Entreri springs a trap. But can Regis survive unscathed?

The companions from Icewind Dale battle pirates on the farted Sword Coast, brave the deserts of Calimshan, and fight monsters from other planes to rescue their friend ... and themselves.

This is Book Three: The Icewind Dale Trilogy.