Films that have insanely good starts but falter off into a mediocre film as it progresses?

In other words, films that are a 10/10 for the first 30 minutes of it, but then for the rest of it are 3/10 to 6/10.A good example I like is The Transporter (2002). The first 30 minutes are some of the best set pieces in action film history; the first car chase around Calais, the first transport job, and the revenge spree in the house after the car is blown up.But after the 30-minute mark, the film just loses all originality and falters off into a regular action hero-type film, and a quite mediocre one at that.What are some other examples of films like this? via /r/movies http://bit.ly/2TwVBVl