Crimson Tides of Tethyr is an NWN1 module created by Alazander, and is available free on the IGN NWN vault. It is part of a series of modules created by Alazander, although you do not need to play the others to fully enjoy this one.
The setting is Tethyr, which for reasons initially unknown has been invaded by the Sythillisian Empire. Your character is an adventurer of some experience, and signs up as a mercenary to fight against the invading humanoid army.
What follows is a great storyline, with a number of memorable moments. Your allies and enemies have great dialog, and the module really does feel like a forgotten realms adventure. The average score out of 10 for this module at the vault isĀ 9.8, and it is a number that is well deserved. I would say this is a must play module, and there is very little chance of even the pickiest player being let down by it.
If there is a module that deserves to be updated and converted to the NWN2 engine, it is this one. Let Alazander know how you feel at his blog.