Do yourself a favor when watching this episode and fast forward through any scenes that do not have Klaus or Tyler in them. Yeah, you'll miss out on some of the explanation of the season's main plot arc (Prof McShady and the quest for Silas and the cure), but that's stuff you can easily catch up on during the recap shown before the next episode. You'll save yourself the mind-numbing tedium of Elena/Damon guilt-laden relationship defining conversation scenes, which stopped being interesting about 5 episodes ago, and Jeremy/Elena therapy scenes, which probably even bored the writers as they wrote it. Cut all that crap out and you have one of the best episodes of the season (too bad it's only about 15 minutes worth of air time). I give it a 9 because it's only about a 2.5 without any Klaus scenes and it's an 11 with only the Klaus scenes.
The Tyler scenes are needed for an even fuller appreciation of how awesome the Klaus scenes are, which, suffice to say, were epic. Joseph Morgan delivered an amazing performance and gave us a really layered look at one of the most interesting characters on TV. Between wooing Caroline, honestly conversing with Stefan about what it means to be immortal, and discovering the betrayal of his hybrid pack, every scene with Klaus was electric. Klaus was truly sympathetic even as he slaughtered his hybrids and murdered Carol Lockwood, not an easy feat for an actor to do. Thank God it was Joseph Morgan doing it and not Paul "I only act by knitting my eyebrows together" Wesley.