You'll need strong music theory knowledge to read and understand everything in Murphy's four articles. To see what they're like, you might start with the last one in the list below, as it's easily accessible through the journal Music Theory Online (link).
On the other hand, the effects of harmony that he talks about are easy to hear in the films he discusses.
The "triad pairs" that are presented in Murphy 2014a are abstract categories representing every possible pairing of major and minor triads. Here is a simple example: M2m in his notation is a major triad -- like C major in the examples below -- followed by a minor triad (D minor here) whose root is two half-steps higher (C to C# is one step, then C# to D is the second step). The effects created by use of any triad pair vary widely, of course. At (a) a relatively brief minor triad is tucked in-between two major triads, an incidental effect or neighbor chord. At (b) the two chords are equal in length, but there is a definite element of contrast, as the upper voices and bass move in opposite directions, following the requirements of older tonal voice-leading rules. At (c), on the other hand, the chords are spread out -- we hear more of each one -- and all the voices move in the same direction. Finally, at (d), we hear C first, then the chords are mingled and we either hear them as layered or as a complex chord over the C bass (it would be a C13 chord with a diatonic 11), then the C chord layer disappears.
Reference: articles by Scott Murphy on film music:
1. Murphy, Scott. 2014b. “Scoring Loss in Some Recent Popular Film and Television.” Music Theory Spectrum 36(2): 295-314.
2. Murphy, Scott. 2014a. “Transformational Theory and the Analysis of Film Music.” In The Oxford Handbook of Film Music Studies, edited by David Neumeyer, pp. 471-499. New York: Oxford University Press.
3. Murphy, Scott. 2012. “The Tritone Within: Interpreting Harmony in Elliot Goldenthal's Score for Final Fantasy: The Spirits Within.” In The Music of Fantasy Cinema, edited by Janet K. Halfyard, pp. 148-174. London: Equinox, 2012.
4. Murphy, Scott. 2006. “The Major Tritone Progression in Recent Hollywood Science Fiction Films.” Music Theory Online 12(2). link.