Even though this story has been teased for several months, Peter Milligan fills it with the unexpected. Constantine himself is caught off-guard by the grisly magical sewer murder (or near-murder, as it were), with which he's faced. He behaves unlike himself and can't explain why, and by the end he is forced to admit that, like it or not, he and his long-lost nephew are being drawn to each other, so he may as well get on board.
Milligan has done a lot to build the size and importance of Constantine's family in this series, and the addition of the mysterious stolen child who may himself be a powerful black magician is a welcome next step in that process. Not to mention that all signs point toward Finnbar Brady, who evidently has no memory or understanding of what's going on. That layer makes the story all the more compelling, because it indicates some larger, even more evil and dangerous force involved, pushing the two Constantine men toward one another for unknown reasons. And the horrid, gory nature of the events of this opening chapter promise an enthusiastically disgusting and high-powered finale.
Giuseppe Camuncoli & Stefano Landini get the gore and filth just right, showing us enough that we can see how severe things are but still leaving it largely hidden or obscured so our imaginations get to do most of the work. This plus the look of deep, genuine shock on the face of the typically unshakable Constantine bring home the seriousness of what's going on, the power and potential of the evil at work. And there is a general gritty roughness to the artwork that goes hand-in-hand with the underlying uneasiness Constantine feels. He's not quite in his right mind, and he knows it, but he doesn't know why, and the edginess of his surroundings underline that feeling of things being unfamiliar even though nothing has noticeably changed.
Where this story is headed is anyone's guess, but since we've known that Hellblazer was headed for this arc for some time, it's nice to see the first issue of it still have plenty of enjoyable surprises. Another twisted branch on the Constantine family tree is growing, but the shape which it will take is still unclear.