The Road Builder (U.S. title: The Night Digger[1]) is a 1971 British thriller film directed by Alastair Reid and starring Patricia Neal, Pamela Brown and Nicholas Clay.

[2] The screenplay was by Roald Dahl based on the novel Nest in a Fallen Tree by Joy Cowley, about two women who are visited by a suspicious handy man.

[3] Maura Prince works part-time as a speech therapist and the rest of her time taking care of her blind, invalid mother, Edith.

Billy Jarvis arrives, claiming he was sent there in place of a neighbor's nephew who was to live with the Princes and work in their garden.

While attending church with Edith, Billy notices pretty, young nursery school teacher Mary Wingate.

That night, while having psychotic flashbacks of being raped by women and taunted for impotency, Billy goes to her home and murders her, then buries her body at a road construction site.

Edith, impatient when Billy doesn't answer her calls, tries to climb the stairs to his room and has a heart attack.

After some months have passed, Billy sees a young female neighbor looking for her dog, and Maura realizes what is happening when psychosis grips him later that day.

Valerie came to help with the lines, but my coworkers did not have the generous spirit of Jack Albertson and Martin Sheen (with whom she had made The Subject Was Roses) and I sensed their impatience when I stumbled.

"[13] In a contemporary review, The New York Times wrote "It begs for empathy for its tortured principals, but despite the clearly dedicated contributions of Patricia Neal, Roald Dahl...Pamela Brown and a young newcomer, Nicholas Clay, the strain on credibility is a good deal more notable than the impact on the emotions";[14] Variety praised the acting but called the film "only moderately successful.

"[15] More recently, a reviewer for DVD Talk wrote "The Night Digger doesn't carry much of a reputation, but I found it highly unusual, and more than satisfying.

[17] The Radio Times stated "director Alastair Reid's neo–Grand Guignol chamber piece exudes a peculiar fascination.