Sprequel 

A movie, book, or other form of entertainment that deals with both the future and origin of a series. Basically a prequel and a sequel combined.

The movie Terminator: Salvation is a sprequel because it deals with the future of John Connor and Skynet, but also deals with events before the orginal Terminator, like the creation of the T-800 Model 101 Terminator.

Sprequel by imnotacritic May 28, 2009

Sprequal

A follow-up film that takes place both before and after the timeline of the original.

Paranormal Activity 2 is a sprequal because it takes place both before and after the events of the first Paranomal Activity.

Sprequal by Vachon Rahl March 3, 2011