Oh, boy. Let me start by saying how much I used to love Kevin Smith. His first five movies are some of my favorites. Jersey Girl wasn't as bad as people remember and Clerks 2 is right up there with his classics in my book. I am thinking that it was when he started smoking weed that I lost interest in his writing. Cop Out was pretty damn bad. Red State, which starts strong, ends in the weakest possible way (rule number one: show, don't tell). So, I'm not surprised I kind of hated Tusk but I am saddened.
Justin Long stars as an asshole podcaster who travels to Canada to make fun of a kid who made a viral video. When that falls through, he looks for anyone he can interview and runs into Michael Parks as Howard Howe. Before you can say "Misery", Long is captured by Parks and slowly transformed into a Walrus through crude surgery. The second half of the movie is Haley Joel Osment and Long's girlfriend teaming up with a never-less-funny Johnny Depp wearing a fake nose and chewing on a Montreal accent.
I would say there are no likable characters in this movie but that would require most of them to be characters and not just one-dimensional sketches. Long is shown in flashbacks being a sonofabitch to his girlfriend and using his podcast to mock others. Depp is ineffective and boorish. Osment isn't even allowed to speak most of the time. The only actor used to good effect is Michael Parks (except for an unfortunate scene where he plays a mentally challenged man). He alone brings the gravitas that would be needed to sell this movie as either a horror or a comedy. Unfortunately, he is stranded on screen and the film fails to become either.
I don't know if Smith will ever return to form (he is still very funny and charming in his talks, so I have hope) but I can say, don't waste your time with this.