At the center of “Brick Lane,” a modest new film directed by Sarah Gavron, is a woman for whom modesty is not just a defining character trait but also a moral principle. Nazneen (Tannishtha Chatterjee), who came to England from Bangladesh as a teenager for an arranged marriage, moves through her East London neighborhood as if determined to attract as little attention as possible. Pulling her sari tightly around her small frame and delicate face, she hurries home with her groceries; once inside her cramped apartment, she ministers quietly to the needs of her husband, Chanu (Satish Kaushik), and their two daughters. Nazneen takes in a lot —Chatterjee’s ever-widening eyes may be her most notable feature — but gives away very little. If she mourns the death, many years earlier, of her infant son, or experiences boredom or frustration with her daily routines, these feelings stay far below the surface. Nazneen quotes a saying of her mother’s: Life is to be endured. Like Emma Bovary, literature’s most famous prisoner of normalcy, Nazneen uses reading as a means of escape. Rather than novels, she pores over letters from her sister, who stayed in their native country and whose life seems to be full of incident, intrigue and romance. ...