I'll be up front and say that if I hadn't known beforehand that Johnny Depp would appear in Tusk under a pseudonym – a "secret" that everybody and their grandmother seems to know by this point – I would never have recognized him. So you deserve some props for that. However, while he's hidden beneath that brilliant makeup, Depp (or "Lapointe") overacts to such a horrific degree that's it's almost unbearable to watch. Which is indicative of the problem with Tusk as a whole: it never seems sure what type of movie it's trying to be.
Let's take, for instance, a late-in-the-game flashback sequence in which his retired homicide detective recalls the time hefirst met the film's villain, played by Michael Parks. I sat in my seat, utterly aghast, as the two actors stared awkwardly at each other, forcing out allegedly humorous dialogue (apparently faux-Quebecois accents are Kevin Smith's idea of biting satire) in a bit that goes on for so long that the unspooling of quantum time ceases to retain any meeting. And then, all of a sudden, Lapointe returns to the present and somberly states that he was once missed an opportunity to save one of Parks' victims. I'm sure you'll agree that there are talented filmmakers out there who can walk the line between humour and tragedy. Kevin Smith, sadly, doesn't seem to be one of them.
It isn't much of a surprise that Tusk's biggest issue is how it treats it's central character, Wallace Bryton of the Not-See Party podcast. [As an aside: did you ever stick around on the set once Depp's makeup was applied, and, if so, did you notice Smith quietly chuckling to himself every time a character mistakes "Not-See Party" for "Nazi Party"? I feel like that would have made for a pretty unpleasant drinking game.]
Anyhoo...as soon as we meet Bryton, he's already such a loud, crude, belligerent asshole (for lack of a better term) that it's impossible sympathize when Parks abducts him and reveals his plans to surgically alter him into a man-walrus hybrid. To be fair, the initial reveal is by far the funniest moment of the film; the group I saw the film with was nearly in tears. And yet, we're also supposed to empathize with Wallace, even though he's the focus of a goofy sight-gag one second, then tearfully reflecting upon his lost humanity in the next. The wild tonal shifts are enough to give you whiplash.
To that point, the ludicrous design of Wallace the Walrus makes it abundantly clear that we're supposed to be laughing at him; Smith never attempts to hide just how artificial the costume really is.
It's odd that such a messy film would have a villain as compelling as Michael Parks. As goofy as the material is, he imbues the character with an interesting mix of madness and sadness, all slowly revealed as the reasons for his walrus-love become apparent. It's captivating stuff, but given how scattershot the rest of the film is, it's a safe assumption that this speaks more to Parks' strength as an actor than it does to the quality of the material he was working with.
I really don't know how I could sell someone on this movie. It certainly doesn't work as a horror movie. Or even a thriller. And yet, there's really nothing funny about it. Here's hoping that your actor-concealment skills are put to better use in the future.