Ernest Cunningham Breaks the Family Code

Ernest “Ern” Cunningham knows exactly how a murder mystery is supposed to work. He makes his living writing instructional books about mystery fiction, and he narrates his own story according to Ronald Knox’s famous rules for detective stories. Ernest promises to be reliable, reveal clues fairly, and never hide information simply to manufacture a twist.

That promise becomes especially important because Ernest’s own family has a complicated relationship with killing.

The Cunningham family’s troubles stretch back decades. Ernest’s father, Robert Cunningham, was involved with a criminal syndicate called the Sabers before secretly becoming an informant for Detective Alison Humphreys. Robert had gathered evidence against corrupt police officers Alan Holton and Brian Clarke, who were connected to the ransom kidnapping of a young girl named Rebecca McAuley.

Before Robert could expose them, Holton shot him dead at a gas station. The Sabers then made sure Robert’s widow, Audrey, stayed silent by kidnapping her five-year-old son, Jeremy. Audrey was told Jeremy had died. In reality, he was abandoned and eventually raised by foster parents, Mark and Janine Williams.

Ernest was only six when his father died, and he grew up believing Jeremy was gone as well.

Decades later, Alan Holton resurfaced in the Cunningham family’s life. Three years before the main story begins, he offered to sell Michael Cunningham, Ernest’s older brother, evidence connected to Robert’s murder. Michael agreed to buy it using money provided by Rebecca McAuley’s parents, who were still searching for answers about their daughter’s disappearance.

But Michael had another problem. His wife, Lucy Sanders, was deeply in debt, so he secretly used $33,000 of the money to help her.

That left him short when he met Holton.

A violent confrontation followed. Holton was shot during the struggle, and Michael struck him with his car. Michael then called Ernest for help. The brothers drove the injured Holton to a snowy field, where Michael finished killing him by choking him.

Instead of protecting his brother, Ernest called the police.

His testimony helped convict Michael, although their wealthy stepfather and defense lawyer, Marcelo Garcia, managed to reduce the consequences to three years in prison for manslaughter. Ernest kept the remaining $267,000 from the deal hidden in a Nike bag.

To the rest of the Cunninghams, however, the important part was simpler: Ernest had betrayed his brother.

A Family Reunion Begins With a Body

Three years later, Michael is finally being released, and Aunt Katherine Millot organizes a mandatory family reunion at the isolated Sky Lodge Mountain Retreat near Jindabyne. The gathering includes Audrey and Marcelo; Katherine and her husband, Andy; Ernest’s stepsister, Sofia Garcia; Michael’s ex-wife Lucy; and Ernest himself.

Ernest is already uncomfortable being around the family that has largely rejected him. Then he learns that his estranged wife, Erin Cunningham, is the person picking Michael up from prison.

Before Michael even reaches the resort, however, the reunion gets its first corpse.

A frozen man is discovered on the golf course. Because nobody initially knows his identity, he becomes known as “Green Boots.” Sofia, a surgeon who has been suspended following the death of a patient, examines the body alongside Ernest and local police officer Darius Crawford.

Sofia quickly notices something that changes the entire situation: charcoal ash is packed inside the dead man’s throat and windpipe. He didn’t simply freeze in the snow. He was suffocated.

The method resembles a series of killings attributed to a serial murderer known as the Black Tongue.

Then Michael arrives—with Erin.

Ernest discovers that Erin and Michael began corresponding while Michael was incarcerated and developed a romantic relationship. Before Ernest can fully process that betrayal, Michael himself becomes a suspect in the new murder. Crawford detains him in the resort’s exterior Drying Room.

But Michael manages to give Ernest the keys to his truck first. Whatever is inside, he says, will explain what has been happening.

The Coffin in Michael’s Truck

Ernest investigates the truck with Erin and Sofia and discovers a wooden coffin in the back.

Inside are two sets of human remains.

One belongs to Brian Clarke, the corrupt former police officer connected to Alan Holton. The other is the small skeleton of Rebecca McAuley, the girl who disappeared 35 years earlier.

The discovery suggests Michael has uncovered something enormous about both Rebecca’s kidnapping and their father’s death. But before Ernest can preserve the evidence, the truck suddenly begins rolling downhill.

It crashes onto the frozen lake and breaks through the ice.

Ernest nearly goes down with it. His arm becomes pinned beneath the heavy coffin, leaving him trapped in freezing water until Erin, Sofia, and Crawford manage to pull him free. The truck and its evidence sink beneath the lake.

The accident wasn’t really an accident. Marcelo, desperate to protect his family from whatever Michael has brought with him, bumped the handbrake and poured hot coffee onto the ice to help send the truck into the lake.

Yet destroying the evidence does nothing to stop the killer.

Michael Becomes the Next Victim

Badly injured, Ernest recuperates inside the lodge while Katherine gives him painkillers. Outside, the blizzard grows worse, trapping everyone at Sky Lodge.

Then Michael is murdered.

Someone breaks the Drying Room window and uses a leaf blower attached to a cylinder running through the snowbank to pump charcoal ash into the sealed room. Michael is tied up and helpless as the ash fills his lungs.

When Ernest eventually opens the door, his brother is dead.

The Black Tongue is at the resort.

As Ernest investigates, more Cunningham secrets emerge. Katherine reveals that Sofia has an Oxycodone addiction and has come to the resort partly to detox before a coroner’s review of the patient who died under her care.

Sofia admits to another secret. To fund her addiction, she stole Marcelo’s $50,000 platinum Rolex and replaced it with a fake. The genuine watch eventually wound up in Alan Holton’s pawn shop.

Hidden beneath its glass was something far more valuable than the watch itself: a microdot containing tiny photographs created by Robert decades earlier.

Michael had been searching for that evidence.

Rebecca McAuley and the Missing Evidence

Ernest travels by snow-tank with resort owner Juliette Henderson and Andy to the neighboring SuperShred Resort, where he meets Rebecca’s parents, Edgar and Siobhan McAuley.

They explain that they hired Michael to recover Rebecca’s remains and obtain the microdot evidence that could finally reveal what happened to their daughter.

Back at Sky Lodge, the mounting deaths and revelations become too much for Lucy. She already feels responsible for Michael being confined in the Drying Room because she suggested putting him there. After seeing the photograph of Green Boots and becoming overwhelmed by guilt and fear, she climbs onto the resort roof and jumps to her death.

By now, Ernest has enough information to understand that the murders at Sky Lodge are tied not only to Michael’s investigation, but to the Cunningham family itself.

He gathers everyone in the library and explains what he has discovered.

Officer Crawford Is Jeremy Cunningham

The Black Tongue has been standing beside them throughout the investigation.

Officer Darius Crawford is actually Jeremy Cunningham, Ernest and Michael’s supposedly dead younger brother.

Jeremy survived his childhood kidnapping and was raised by Mark and Janine Williams. Years later, Alan Holton tracked him down and told him who he really was.

Learning about the Cunninghams warped Jeremy’s idea of family. He became fascinated by the fact that members of his biological family had killed people and began to see murder as something that connected him to them.

When his foster parents admitted the truth about his origins, Jeremy murdered Mark and Janine by suffocating them with ash inside their car. They became the Black Tongue’s first known victims. He later killed Alison Humphreys, Robert’s former police handler.

When Jeremy learned about the Cunningham reunion, he headed to Jindabyne. He murdered Brian Clarke—the man initially found as Green Boots—and used his access to law enforcement to insert himself into the investigation under the identity of Officer Crawford.

Jeremy’s real goal was to reunite with his biological family.

He approached Michael in the Drying Room expecting Michael, another man who had killed someone, to welcome him as a brother. Instead, Michael rejected Jeremy’s glorification of violence and refused to hand over the microdot evidence.

Jeremy killed him for it.

The Library Burns

Once Ernest exposes him, Jeremy attacks.

He grabs a heavy fireplace poker, then pulls a burning log from the hearth and throws it onto the carpet. Fire races through the book-filled library as the confrontation turns violent.

When Jeremy attacks Katherine, Andy fights back. He charges Jeremy and strikes him hard across the jaw with a poker.

Jeremy falls backward through the collapsing floorboards and into the burning level below.

The surviving family members escape as Sky Lodge burns and collapses around them.

Outside, Ernest finds his badly injured younger brother in the snow. Jeremy asks whether Ernest ever dreams about choking. Ernest tells him that he does.

For Jeremy, it provides one last sense that he shares something with his brother.

Then he stops breathing.

The Final Secret on Michael’s Bingo Card

Even after the Black Tongue is dead, one mystery remains: what really happened to Rebecca McAuley?

Divers eventually recover the coffin and Rebecca’s remains from the lake so her body can finally receive a proper burial. But Ernest realizes that Michael did not leave the crucial evidence inside the truck.

Using a jeweler’s loupe, Ernest examines Michael’s bingo card and discovers the missing microdot glued beneath one of the pen strokes.

It contains 16 tiny photographs.

And those photographs reveal the final truth.

Edgar McAuley killed his own daughter, Rebecca.

Thirty-five years earlier, Edgar murdered her and staged the crime as a ransom kidnapping. The evidence Michael died trying to recover ultimately exposes Edgar, who is arrested for Rebecca’s murder.

The reunion leaves the Cunningham family devastated but finally free of secrets that have haunted them for decades. Ernest gives up his portion of the remaining $267,000, using money to pay for Lucy’s funeral and help her family. Sofia completes rehab with Katherine supporting her through recovery.

Erin and Ernest accept that their marriage is over and begin amicable divorce proceedings.

Most importantly for Ernest, his relationship with the surviving Cunninghams begins to heal. Audrey and Marcelo reconcile with him, and the family starts having weekly dinners together.

After years of being treated as the Cunningham who betrayed everyone else, Ernest finally has a place in his family again.