The phrase "entire subplot" refers to a secondary storyline within a larger story. It usually involves its own set of characters and events that are separate from the main plot. Full definition
It is also apparent that some major and last - minute editing was performed; one entire subplot involving Hunt and Mrs. Phelps is so obscured throughout the film that its sudden reappearance at the end of the film is as much a surprise as a clarification of audience expectations. (nitrateonline.com)
Not only are entire subplots from the book eliminated, but several characters have been cut, too. (eclipsemagazine.com)
The rest of the Harry Potter cinematic saga has been racing against the clock since 2001, cleaving away entire subplots and characters to fit an average running time of 150 minutes. (scifimoviepage.com)