A lot of good movies come in threes. For Example, Lord of the Rings, the Matrix films, and Pirates in the Caribbean. As we were walking into the theater, and I asked my wife how many good fourth movies she could think of. Her answers were Harry Potter and Episode IV. We disqualified episode IV since it was actually the first movie in the series. You can think of just as many series that really should have stopped after three movies. Star Wars, the old Superman films, Indiana Jones, Die Hard, Alien, and others.
I am a huge Alien fan. The original is probably my favorite movie of all time. None of the sequels were very good, but the fourth one, directed by a french music video director, was a complete embarrassment. When they announced that McG, who is a music video director I have never heard of, was directing Terminator Salvation, that tempered my expectations a little bit. In addition to videos, McG also directed Charlie's Angels, Charlie's Angels: Full Throttle, and We Are Marshall- three undeniable piles of crap.
So despite the incredibly good trailers out there, I tried to walk into Terminator Salvation expecting disappointment. I walked out happy and anxiously awaiting the 5th film in the series. T4: Salvation isn't perfect but it is a good summer action flick and captures some of the compelling themes of the series very well.