Our intrepid team were asked to investigate the disappearance of Brian Burnham, a young man who had taken a job in infamous Innsmouth, MA, but supposedly turned to crime before escaping police and fleeing to parts unknown. After some questioning of local sources and leads, the group reluctantly made their way to the ill-regarded town, where things turned out to be just as bad as they expected...
This went really well given the players were all quite familiar with Lovecraft's story. They managed to play ignorant and get themselves into the correct mindset. I think Innsmouth is well-presented in the sadly out-of-print Escape From Innsmouth supplement, and it gave me a wealth of material to draw from. Mr. Waite's wife was an especially effective surprise.
I have to note our group is a very practical one. There was no truck with rescuing Ruthie ... her boyfriend's protestations were silenced (twice!) with a well-placed punch in the face. As for the Innsmouth police, although they've always been careful about dusting mere mortals, I guess hybrid deep ones don't count. To get to the prisoner's cells, they just locked the door to the police station and killed the cop on duty! Yow!
It ended with a quite literal escape, with a carful of Innsmouthers in pursuit, finally derailed by a good shot from Judge Plamondon. I downplayed the number of pursuing vehicles, not seeing how enough time would have been available to stir up the whole town, but spiced up the final chase by throwing in a last-minute attack by full-on deep ones (one of whom jumped onto the car and started clawing away before getting dispatched by a pistol shot), and something else which the team was fortunate to escape and not get a good look at.
A lot of fun with this one, and even the endless fish jokes didn't quite take the edge off it.