Have you seen "Death Becomes Her"? "The Haunted Mansion"? Any vampire movie ever? Any Johnny Depp movie ever?
Then no need to see "Dark Shadows." Just mix all of those movies together in your head and you can pretty much imagine exactly what the movie was like.
I'm not a huge movie goer. I prefer to watch movies in the comfort of my own home surrounded by my fur family and with access to all kinds of delicious snacks. But this movie we were in the mood for a movie and "Dark Shadows" had the most desirable starting time and movie location.
Johnny Depp has a particular character he likes to play and he plays it well. So I don't think anyone will be surprised to see him as a dark character hailing from 1700 England. I like Depp, I think most of his movies are fun and I also tend to have a slightly darker sense of humor. But I even found his character a little confusing as we are supposed to accept his very proper manner of pursuing women even while randomly 'hooking up' with several others. I assume it was supposed to be assumed that the women who had his hearts affection was of his class, while the others weren't, but since she was actually the family's nanny, even this falls apart. More likely, Hollywood didn't think there was enough sex in the movie so threw it in for ratings/viewership/whatever. Another reason I don't like watching movies in theaters, you may be cool with your 7 year old daughters watching those scenes, but it makes me really uncomfortable.
I'd say skip this one especially in the theater. If your a huge Depp fan, rent it from red box.