MacGuffin Save the Clock Tower

You see, I am rewriting my script that I plan to direct in April, and so, I am freshning up on the basics... trying to impose creative writing elements from 2 script on my script; Casablanca, and Back to the Future!

Taken from wikipedia:

A MacGuffin (sometimes McGuffin or Maguffin) is a plot device that motivates the characters and advances the story, but has little other relevance to the story.
The director and producer Alfred Hitchcock popularized both the term "MacGuffin" and the technique. According to the Oxford English Dictionary, Hitchcock explained the term in a 1939 lecture at Columbia University: "[W]e have a name in the studio, and we call it the 'MacGuffin.' It is the mechanical element that usually crops up in any story. In crook stories it is always the necklace and in spy stories it is always the papers."

The element that distinguishes a MacGuffin from other types of plot devices is that it is not important what object the MacGuffin specifically is. Anything that serves as a motivation will do. A true MacGuffin is essentially interchangeable. Its importance will generally be accepted completely by the story's characters, with minimal explanation. From the audience's perspective, the MacGuffin is not the point of the story.
The technique is common in films, especially thrillers. Commonly, though not always, the MacGuffin is the central focus of the film in the first act, and then declines in significance as the struggles and motivations of the characters take center stage. Sometimes the MacGuffin is all but forgotten by the end of the film.
Because a MacGuffin is, by definition, ultimately unimportant to the story, its use can test the suspension of disbelief of audiences. Well-done works will compensate for this, with a good story, interesting characters, talented acting/writing, and so on. Inferior films, which fail in those areas, often only highlight a MacGuffin, sometimes to the point of absurdity. MacGuffins may be acceptable to the general audience, but fail to be believable for experts in the subject matter (such as a particular technology, or historical detail).

The example of Casablanca: The letters of transit in Casablanca are considered a MacGuffin by many, including Roger Ebert, as he notes in his audio commentary on the movie's DVD. [18] However, Dan Ramer of DVDFile.com argues, "The letters might be considered a Hitchcockian Macguffin, but they're more than that. A Macguffin is a distraction, a mechanism to provoke the story the filmmaker wants to tell; here they play a vital role. Like the stolen plans for the Death Star, they will provide the means for the film's resolution." [19]