Theatre of the Damned begins with an absolutely gorgeous colour picture of a figure posting an advertisement for the eponymous theatre on some board in a Warhammer city, with the slight hint of mutation or disease upon the hands on the edge of frame. This sets the tone of the adventure very well: it is full of mutation and little details that help add to the creepy, dark atmosphere. However this and the central idea are let down by some weak plotting which fails to give the story true coherence.
The central idea is a good one: an underground theatre (both literally and metaphorically) dedicated to mocking the nobles of Nuln with shocking disregard for modesty and personal reputation, which many nobles attend "incognito" to see just how shocking it is. Equally nice is that the theatre's scripts are written by a mutant and the underground nature of the theatre allows mutants to perform in it, so that the nobles attending are in fact paying handsomely to watch the people they so publicly scorn, and whom they pay their taxes to have hunted down and killed.
Of course, mixing with such ideas is tricky for an adventure because WFRP is unclear on morality and sometimes not even a GM can be sure how his players will react to those touched by Chaos. This adventure could, at any moment, be derailed by vigilant Sigmarites doing their lord's work and slaughtering everyone around them - and without remorse.
Given the extremely suspect nature of the theatre, too, a strong reason is needed to get the PCs to even go there, let alone haggle with dangerous crime lords for tickets as they must in the first part of the adventure. But no such hook is provided, with the authors assuming PC curiosity or a few crowns will be enough to direct them to walk through the sewers to a place they know is full of criminals, and one in which the Knights Panther are trying to expose. For that matter, the difficulty of reaching the theatre - having to carry animal skin marked with a tattooed ticket, walking through the sewers - makes it seem unbelievable that nobles would really slum it that much.
Also unbelievable are some of the character's actions, particularly the main protagonist who stands up in the third act and goes "by the way, my brother writes all these and he's a mutant, now I must go rescue him, bye!". He also announces that his mutant friends will now attack the nobles. This is followed by an unbelievably convenient raid on the theatre by the Knights Panther (or rather a Knights Panther and his fanatical servants) wherein the players apparently face the tough choice of which side to join. Given that the Knights are tough customers and will kill anyone inside, and given that the mutants just announced they plan to kill the (semi)innocent nobles, I can't imagine them giving a damn about the mutants.
Which would be fine but the final set-piece depends on the PCs interrupting a Mexican stand-off between the protagonist and the mutant-hunting Knights Panther, and facing what is supposed to be a dramatic decision. Perhaps if the PCs had read the dramatic full story of this actor and his mutated brother and his brother's rejected love, they might care. But this adventure suffers from being full of background without providing any way for that background to reach the ears of the PCs.
While it is fun for the PCs to be stuck in the middle of a battle between A and B, instead of being one or the other, the end result in Theatre of the Damned is that A and B are the stars of this story, and the PCs are just tourists, passing through. As such it is a poor adventure, but it does make an excellent location-plus-adventure-seed write-up, where said location is the Theatre itself - how and where it operates, its twisted staff, it's criminal networks and the entertaining route needed to visit it.
If you're looking for a location to spice up a crime-themed Nuln campaign, the Theatre is definitely worth a look. As an adventure, however, it doesn't cut the mustard.
