Pete Hamill is famous for numerous reasons. He was a pioneering newspaperman, and remains a provocative commentator and celebrated memoirist. He was a man about town who befriended the Kennedys and later stepped out with Jackie Onassis. He is also an unofficial ambassador for New York, the city where his Belfast-born parents raised their large family. All of this sometimes makes it easy to forget that Hamill is a brilliant writer of fiction, who (as has often been said about Philip Roth) is getting better with age. Hamill's recent novels have been ambitious efforts, and have only strengthened his reputation as one of New York's great chroniclers. Joyce had his Dublin, Dickens had his London and Hamill has New York. Hamill's latest, "North River," gets its title from the old-time name for the Hudson River. Not far from the river's frigid waters, in 1930s Greenwich Village, lives Dr. James Delaney, a scarred veteran of World War I who cares for the neighborhood's sick and suffering, even though he's unable to heal his own wounds. Aside from his service in the Great War, Dr. Delaney has also lost his wife and daughter. To make matters more difficult, the winter of 1934 (when "North River" is set) is turning out to be particularly cold, and there seems no end in sight to the Great Depression, which is ravaging the locals, who are unable to pay for the crucial medical services which Dr. Delaney still provides. Amidst all of this, an infant (belonging to Delaney's daughter) has been left on his stoop. Despite all of this adversity, after Dr. Delaney hires an Italian immigrant named Rose to help out, he unwittingly creates a surrogate family to replace the one he has lost. Just as a tenuous sort of peace is established, however, it turns out that Delaney's compassion and selflessness may have gotten him into serious trouble with a local gangster. In the end, North River has the feel of a tough yet beautiful ballad, rich with local details and color, and unflinching in its depiction of life's difficulties. With "North River," Hamill has proven yet again that he is among the top novelists working today. ($25.99 / 352 pages / Little, Brown)