The following version of this book was used to create this study guide: Haigh, Jennifer. Heat & Light. HarperCollins, 2016.

The novel, which is told through the third-person omniscient perspective, opens with a short prologue that introduces Bakerton, Pennsylvania, as a former coal-mining town that was first founded in the Pennsylvania Oil Rush in the late nineteenth-century.

In 2010, when the first section of the novel begins, Bobby Frame is leasing agent for Dark Elephant, and he travels to Bakerton to convince residents to sell their mineral rights. He drops in on the Devlins, who are central characters throughout the novel. Rich, a correctional officer, and Shelby, his young wife, sign the lease for $25 per acre right away. While they sign the leases in Pennsylvania, the Dark Elephant shareholders approve drilling in Pennsylvania, and Kip Oliphant, the CEO, is eager to get started.

The next section begins two years later, and Rich is frustrated that drilling on his land has not yet begun. Other people in town have made millions on royalty checks while he has been picking up extra shifts at the prison and working at the Commercial Bar afterwards to help out his father, Dick, the owner. That weekend, Shelby brings her daughter Olivia to church. Shelby brushes Olivia’s hair carefully and lays out a white dress for her to wear, and she is pleased that her fellow parishioners notice when they enter the church, Living Waters, their church, is run by Pastor Jess Peacock, who took over when her husband passed away a few years ago.

Rich sees Bobby Frame in the bar one day the following week, and Bobby tells Rich that the issue is not enough of his neighbors have signed. Rich recruits help from another neighbor who has signed a lease, and visits Mack at her farm, Friend-Lea Acres. Mack is tempted, but her partner Rena is steadfast. They own an organic farm and they cannot risk signing a lease.

Even though there is no lease on their own property, the drilling in Bakerton still affects their business. Farm-to-table restaurants drop the Friend-Lea milk and cream, and Rena is worried. During a delivery at an organic market, Rena meets Lorne Trexler, a geology professor at Stirling College. He encourages Rena to take action and they plan to organize a meeting for Bakerton residents.

After another lease is signed, drilling finally begins on the Devlin farm. Meanwhile, Pastor Jess begins dating the rig manager, Herc. She invites him for over for dinner after bumping into him in Walmart, and the pair share a bottle of wine and talk about Herc’s experiences growing as a pastor’s son and Jess’s marriage. Herc does not disclose the fact that he is presently married.

The next section of the novel is set on Three Mile Island in 1979. That year, a nuclear power plant malfunctions and leaks water contaminated with radioactive Cesium-137. Fifteen thousand people live within a mile of the plant, and one of them is Wesley Peacock. He is homeschooled by his mother, Bernadette. His father Gene insists that they do not need to evacuate, so the Peacocks stayed.

That same year, Mack meets Rena in Bakerton. Rena works at the local Dairy Queen and brings her young son Calvin to work. Mack comes in for a daily lunch and invites Rena and Calvin to sit with her. In San Francisco, Kip Oliphant attends a self help seminar that empowers him and ultimately inspires him to work for his father’s company, Darco Energy.

In July of 2012, Darren Devlin, Rich’s younger brother, returns home after years of living in Baltimore. He originally moved for school, but eventually flunked out after developing a drug problem. Now, he works as an addictions counselor at Wellways, where he completed treatment. With Darren in town, the Devlin family throws a barbecue for Dick, but the family gathering is interrupted by the intense, thunder-like roar of the drill rig.

Lorne Trexler also travels to Bakerton, and he joins Rena in hosting a community meeting in the Bakerton Public Library. Shelby attends, concerned about the smell of water after the drilling begins. Lorne suggests that she get it tested right away. After the meeting, Lorne and Rena go out to dinner and talk late into the night. They continue to talk on late-night phone calls, about the action against drilling in Bakerton and about themselves.

The next section of the novel contains a series of flashbacks. In 1988, as a young geology professor at Stirling, Lorne Trexler begins an affair with his student, Amy Rubin. In 1992, Mack, Rena, and Calvin visit Penn State, where Mack attended a few semesters of school and where Rena hopes her son will go. The next section is a high school history essay from 1995 submitted by Shelby. In 2004, Darren is in rehab at Wellways working on Step 8, making amends with those he has crossed. In 2005, Wesley Peacock dies of cancer.

By August of 2012, the Devlins are using bottled water to wash dishes, cook, clean, and do laundry. The water from their well has an offensive, worrisome odor, and Shelby will not risk having her children get sick. Darren relapses on meth with a high school girlfriend and returns to Baltimore. Rena joins Lorne at a protest at a SUNY school and becomes disillusioned with the campaign. The signs and flyers and speeches call for action, but they offer no solutions.

At this time, Kip Oliphant and Dark Elephant are in trouble. Kip has a number of lawsuits against him, and he is removed as CEO. Dark Elephant stocks plummet, and the drilling projects in Bakerton are cut to save funding.

That fall, the drill rigs are silent and the workers have left town and returned to their families. Rich is relieved that Dark Elephant is paying for a clean water tank for the time being, but, ultimately, he feels that he has already lost. His dream of farming was only possible to achieve on his own land, and the drilling has made that impossible.