Rapid moral degeneration, cannily codified

"Sins" isn't an easily digestible "love" story. The volatile central relationship and the priest's rapid moral degeneration are cannily codified by good performances.
For virtual newcomers, Shiny Ahuja and Seema Rahmani are surprisingly fluent in exploring the dark side of lust and love.
Though a trifle awkward in his demeanour Ahuja's expressions change from anxiety to brutality with remarkable fluency.
Rahmani is restrained and effective in conveying both her character's vulnerability and cunning.
What comes in the way of their performances are the speech patterns - the thickly laden "Keralite" accents often go awry and end up coming in the way of emotions.
What saves the day is the relatively quiet soundtrack punctuated by fits of Williams' flinch-inducing fury.
The sequence at the girls' hostel from where William calls Rosemary away on the pretext that her mother is ill is remarkable.
"I'm ill I'm suffering!" bellows William before tearing Rosemary's clothes off.
The explicit depiction of anxieties that underline the clandestine liaison is keenly contoured in the two protagonists' body language, and the way the director silhouettes them in mid close-ups.
"Sins" is by no means an outstanding piece of work.
But its essentially scandalous theme is underscored by moments of structural serenity and a quiet subtlety that avert the imminent danger of surfacing salaciousness.
The seaside location - almost replicating Ramesh Sippy's "Sagar" - secrete a great deal of unspoken turbulence.
source :
http://www.indiaglitz.com/channels/hindi/review/7455.html

Could you please explain to me the emboldened parts?