With The Little Drummer Girl, John le Carré has thrown off his winter cloak and let his limbs flex. Unlike the Smiley novels, which have a burrowing, circumspect determination, The Little Drummer Girl doesn't read as if it were written with mittens. The book feels as if it were dashed off with the zealous haste of a reporter filing for a deadline. Once the dread Karla had been flushed from his lair like a sick, shivering animal at the close of Smiley's People …, le Carré must have sensed it was time to strike down the tents of the Circus and push on to a larger, more turbulent arena—the Middle East.

Yet this novel is far from a severe break from le Carré's previous preoccupations…. With its secret sharers and frequent stresses on terrorism as the theater of the real, The Little Drummer Girl is a rugged...