Shopping period doesn’t leave much time for pleasure reading. Luckily, good books are often made into decent movies. I haven’t read Ian McEwan’s highly acclaimed novel, but from all accounts, director Joe Wright’s (“Pride and Prejudice”) adaptation certainly does it justice.

“Atonement” tells the tragic story of two lovers who are torn apart by a meddlesome and ignorant 13-year-old girl, Briony Tallis (Saoirse Ronan). While running through her 1930s country home, Briony mistakenly witnesses an altercation between her sister, Cecilia (Kiera Knightley) and her housekeeper’s son, Robbie (James McAvoy). Later that night, Briony attempts to protect her sister by wrongfully accusing Robbie of rape, sending him first to prison and then to the front line of World War II. Robbie and Cecilia spend the next five years struggling to reunite, while Briony comes to terms with the consequences of her insidious lie.

Visually, Wright’s portrayal of the characters’ loss of youth compliments the story’s transition from carefree to tragic. Briony’s pale, stone face and virginal clothing clearly represent her lack of real-world experience and her own self-importance. As she ages, her clothes lose some of their purity, and her face betrays more emotion, as if her self-righteousness has broken and she has — at least marginally — understood the consequences of her action. At the same time, Robbie, who began as an idealistic housekeeper, transitions to a dirty, tormented soldier. The earthy colors that happily suited him at the beginning of the movie soon seem to depress him, illustrating his extreme circumstances.

When Robbie arrives at the retreat of Dunkirk, an epic, five-minute, single shot of absolute pandemonium begins. The chaos present on this beach reminds one of the initial beach scenes in “Saving Private Ryan,” and with equal emotion transports the viewer to a setting of absolute despair. In this one powerful scene, the viewer sees cavalry shooting horses, drunks looting bars, a bandstand full of depressed soldiers. There is a sense of the all-encompassing feeling of despair, for the lovelorn Robbie personally and for the defeated soldiers with him.

“Atonement,” for all its virtues, is not perfect. Numerous times the plot jumps around in such a way that it becomes difficult to tell when chronologically an event occurs. Yet this flaw seems a necessary evil in a film so concerned with conflicting perspectives. There is no way to depict an event from multiple points of view without some unclear jumps, and the viewers can soon reorient themselves within the movie.

Knightley and McAvoy also disappoint in their portrayal of Robbie and Cecilia’s doomed love. They seem more like close friends, or siblings, rather than star-crossed lovers. Yet their mediocre performances are overshadowed by Ronan’s, Romola Garai’s and Vanessa Redgrave’s renderings of Briony. The three of them each embody one stage of Briony’s growth: first immature and self-righteous, then self-loathing, and ultimately repentant. Redgrave’s heartfelt performance, especially her deliverance of a final and unexpected plot twist, certainly atones for Knightley’s and McAvoy’s mediocrity.