Its definitely safe to say that the third film is the weakest in the franchise.  All 3 of us decided to sit down and watch this one together, Brandyn and Myself being fans of the series, Vaughn being a newcomer. Its safe to say for a newbie to the franchise it probably turned him off to the series.  This one was... Strange to say the least.  Lets break it down short to short.  Now the wrap around segment in this film is called vicious circles, being the weakest of the three segments we'll come back to that one later.
The first segment is called Dante the Great.  This was easily the best of the three segments, as it was told from a different point of view then the rest.  A woman, the magicians assistant of Dante the Great is talking to the police about disappearances and murders that Dante is a suspect in, so its not always being directly filmed by a person but rather by an interrogation room camera, which was slightly different and alright in my book.  The story behind Dante is he was a failed magician, util he finds a cloak that gives him access to real magic, the catch being that he has to feed the cape whenever its hungry.  GUESS WHAT ITS HUNGRY FOR. That's right.  Humans.  Blood, or people, it doesn't really specify.  But, the woman is picked up by the police and asked questions, she gives them their answers, and we see the kind of stuff that Dante can do, some pretty cool stuff, which turns into some pretty demented stuff when he splits a rabbit not unlike a banana.  This honestly was the strongest of the segments, and had the greatest climax and payoff.  The ending was entirely a cop-out though.
Segment two! Segment two is called Parallel monsters.  This was the weakest outside of the wrap around.  This segment is all about a guy who creates a portal to a parallel dimension, but something is slightly amiss with this universe.  So basically, he opens this portal into what looks like an exact replica of a mirrored version of his reality.  He has a conversation with the alternate reality version of himself, and the two decide to switch places for fifteen minutes.  Fifteen minutes, and then they come back.  Those fifteen minutes are incredibly detrimental to the way that these guys lives play out.  So the guy in universe A see's this exact mirror image of his home, except for one thing, A satanic picture in the place his wedding picture was.  I know what you're thinking, and no he did not immediately turn around and leave.  He instead goes deeper into the home, to find his alternate dimension wife, with two guys preparing for some sort of ritual.  Again, why didn't he just leave.  So, some stuff happens, he ends up scaring the guys off, and when he goes outside they chase him down, and put, literally the best way to describe this, a demon lobster penis in his face.  Turns out this alternate dimension is full of satanists that have possessed genitals.  Meanwhile, his alternate reality version tries to put his demon penis in universe A guys wifes face.  The short ends with the two guys both being killed, one death by cunnilingus, the other death by repeated chest stabbing.  Super lame indeed.  Super lame indeed
The Third segment! Easily the most put together of the three.  This one is called Bonestorm.  It is literally a bunch of dudes filming themselves skateboarding, and they accidentally summon a death cult.  I cannot describe to you how, outside of this, there is nothing to it.  Its really well coreagraphy wise, outside of that its pretty dumb.
Now for the wraparound.  This thing had one meaning, and the meaning for the real world was lame.  The inside the film meaning was pretty neat.  Its about this guy trying to record viral videos, and become internet famous.  Eventually, weird stuff is happening, and film segments from the other 2 films start to play on his phone in flashes.  his girlfriend gets possessed by a spirit, that kidnaps her and he goes to get her back, chasing the truck that took her.  He finally catches the truck, and the posessed girlfriend tells him to upload all the videos to the internet, making it easier for more videos to be made, killing more people in the process, eventually he does it, finds his girlfriends life less corpse, and he randomly dies of a nosebleed. A nosebleed.
All in all, like I said, this one was the weakest of the films.  I didn't hate it, but I wouldnt recommend it like I recommended the other two.  If you were gonna watch it... Eh.