It’s a Christian charity group that builds homes for homeless people across America.
Arthur Mitchell is a prominent leader and volunteer with the organization. He’s also a dangerous serial killer in the guise of a pious and venerable religious man. He uses “Four Walls One Heart” as an alibi when he travels to other states in order to carry out his kill cycles. Each cycle consists of four separate M.O.s. The first victim is always a ten-year-old boy that Arthur drugs and buries alive in cement at a construction site. The boy remains unconscious, hopefully ensuring a painless death.
Arthur is being stalked by Dexter Morgan at the Sacred Fellowship Church service, After the sermon, Arthur hands out flyers to the churchgoers for a “Four Walls One Heart” project in Miami. Dexter introduces himself to Arthur as “Kyle Butler” and accepts a flyer.
Dexter shows up at the build site and Arthur greets him enthusiastically as “Kyle.” He hands a hammer to Dexter, who notes its make and model. After they nail up a few boards, Dexter walks over to the water cooler and introduces himself to Arthur’s son, Jonah. The young man is friendly and seems to enjoy working at the sites with his family. He tells Dexter that his parents are awesome and they never fight. Jonah says his father even gave him his prize convertible. “Best dad ever,” he insists. When Jonah notices his father looking their way, he hurries off, remarking that his father doesn’t like idle hands.
Dexter and Arthur are in Tampa to work at a build site. However, Dexter’s true objective is to kill Arthur. He sets up a kill room in his hotel room’s bathroom, and then breaks into Arthur’s room to capture him. However, he’s not there. Dexter hurries to the parking lot and finds Arthur’s van, but his tools are missing. Dexter assumes that he walked to the build site, and takes off running.
When he arrives at the site, Dexter hears the thud of Arthur dropping his tool belt on the roof and looks up. Dexter doesn’t grasp Arthur’s intentions until he sees him empty the last of his sister’s ashes onto the ground below. As Dexter runs toward him, Arthur spreads his arms. Dexter lunges forward and grabs him as he falls. The glass vial drops and shatters. Arthur begs Dexter to let him go, and Dexter wonders why keep him alive, just to kill him. Arthur is about to slip from his grasp when construction volunteers run over and hoist him up to the roof. Arthur looks at Dexter and gasps, “I thought God sent you so that I could save you. But God had another plan. He sent you to save me.” Everyone present on the roof treats Dexter as a hero.
Dexter is on a desperate hunt to find Arthur before he kills Scott Smith, the boy he kidnapped from the arcade. He checks vacant houses for sale and the construction site, but finds nothing.
After Dexter discovers the fallout shelter, he returns to the site after dark finds Arthur about to bury Scott alive in a pit filled with wet cement. The drugged, unconscious boy has been zipped inside a sleeping bag. When Dexter tries to stop him, Arthur kicks the boy into the wet cement. The bag slowly sinks as the two men fight each other. Dexter gets the upper hand and knocks Arthur down with a blow from a shovel. He then pulls the sleeping bag out of the cement in time to rescue Scott. While Dexter is distracted with the boy's rescue, Arthur escapes.
The homicide team descends on a Four Walls build site and the cadaver dogs find a buried body bag. Vince Masuka climbs into the pit and rips the bag open, recoiling from the smell. It’s a gray and shrunken corpse. Musaka reports that the victim looks to be about ten years old, and is wearing pajamas. LaGuerta goes off to get a warrant, and Angel orders Debra to start a list of everyone who has ever volunteered for “Four Walls One Heart” nationwide, and cross-check the names with Trinity cities.
- Arthur Mitchell
- Fallout Shelter
- Jonah Mitchell
- Kyle Butler (alias)
- Sacred Fellowship Church
- Scott Smith
- Tampa Hotel