I think the problem here is that some reviewers are too used to shows that deliver the punchline in the first few episodes because they're so scared of cancellation.
Thankfully Haven is bucking that trend; they are opting for a slow build up. Great for viewers like me who remember how well that worked for shows such as the first season of the 'X-Files' and also current shows like 'Fringe', but not so good for the younger people used to instant gratification with tv and who don't like waiting to see what happens.
Hopefully the writers won't bow to the pressure to make Haven move along more quickly. It would ruin a very intelligent show that's aimed at people who want to think things through rather than have the answers handed to them on a plate.
This episode was a classic case in point - it made you think right up to the end. Stephen McHattie was excellent as he always is and I'd like to see more of his creepy character in the future.