Thomas Babington "Babe" Levy (Dustin Hoffman) is a history Ph.D. candidate and avid runner researching the same field as his father, who committed suicide after being investigated during the Joseph McCarthy era. Babe's brother, Henry (Roy Scheider), better known as "Doc", poses as an oil company executive but, unknown to Babe, is actually a U.S. government agent working for a secret agency headed by Director Peter Janeway (William Devane).

East 91st Street and 5th Avenue, Manhattan.

otsoNY Comments: The fence which run around the reservior has since been replaced by an iron railing fence.

Pathway (near Jacqueline Kennedy Onassis Reservoir) Central Park, Manhattan.

Central Park Zoo, Manhattan.

Cherry Hill, Central Park, Manhattan.

Bethesda Terrace, (Mid-Park at 72nd Street) Central Park, Manhattan.

Thomas Babington's Apartment, 435 West 47th Street (btw 9th and 10th Avenue) Manhattan.

otsoNY Comments: Although the street sign clearly states that the location is West 94th Street, it is in fact on the Upper East Side of Manhattan at 76th Street.

East 76th Street and Lexington Avenue, Manhattan.

Diamond Shop, 36-42 West 47th Street (btw 5th and 6th Avenues) Manhattan.

South Gate House, Jacqueline Kennedy Onassis Reservoir, Central Park, Manhattan.