Michael Bay's Transformer movies are unique in that they always get bad reviews but make a fortune at the box office. Is this just an example of critics being out of touch with audiences? Or is it a testament to the power of Hollywood marketing?

Mark WalhbergMark Wahlberg stars in Transformers: Age of Extinction

The first movie, 2007's Transformers actually had a fairly strong critical reaction, earning a 57% positive rating from critics and a whopping 86% from audiences. There has been a significant drop for both critics and audiences for the three sequels: 2009's Revenge of the Fallen pleased only 19% of critics and 58% of the audience, followed by 2011's Dark of the Moon with 36% critics and 56% audience, and this summer's Age of Extinction is at 17% critics and 58% audience.

More: read our review of Transformers: Age of Extinction

The real answer probably lies with the audience of fanboys who watch movies like this over and over until they figure out what's going on. They help boost the films' box office performance, which funds sequels of ever-increasing scale.

So in China, where much of of Age of Extinction was shot, the film has become the all-time box-office champ after just 12 days of release. And by completely recasting this year's movie with all-new actors, Bay proves that maybe what these fans really want are the mammoth effects sequences. Perhaps with the fifth film he can dispense with the actors altogether.

More: watch the trailer for Transformers: Age of Extinction