The Tunnel (2011)

The film is presented as found footage interspersed with interviews after the events.

In the midst of drought and water shortages, the Government of New South Wales plans to recycle millions of liters of water trapped in abandoned train tunnels beneath the heart of Sydney. However, the plan is cancelled without explanation to the public. There are rumors of homeless people taking shelter in the tunnels going missing.

Journalist Natasha, suspicious of a government cover-up, decides to pursue the story to help her difficult career. She recruits her crew, producer Peter, camera operator Steve, and audio engineer Tangles. They interview a homeless man, Trevor, who used to take shelter in the tunnels; however, when asked if something happened to him or friends of his there, Trevor suddenly breaks down into panic, and provides no answer.

Natasha takes her crew to venture into the tunnels to develop their documentary and investigate the disappearances; she does this without warning their boss. After being denied entry by a security guard, they find an alternate entrance. While exploring, the group come across abandoned squats, and old air raid shelters, discovering their map does not cover all the tunnels.

At an underground lake, Natasha provides her commentary before Tangles hears strange noises through the audio headphones. They enter an air raid bell room, where Natasha strikes the bell to capture footage of the resonating sound. Due to the bell sound distorting the audio, Tangles takes the microphone to an adjoining room to adjust the sound levels. After Natasha strikes the bell again, Peter hears something disturbing and Tangles' audio cable is suddenly pulled away through the opening. The others rush to the room, but Tangles is missing.

In the present day interview, Natasha hears the recording for the first time, where Tangles' muffled screams can be heard as he is dragged away into the tunnel.

Back in the bell room, the group find their equipment has disappeared. While searching for Tangles, they find a room with large amounts of blood on the wall and Tangles' torch. Natasha finds her night-vision camera has recorded a creature stalking them from the darkness.

While returning to the surface, the group encounter the security guard, who orders them to follow him out. The creature suddenly pounces and rapidly drags him away. Natasha, Peter and Steve flee, hiding deeper in the tunnel system. Realizing their only way out is through the entrance, they quietly make their way back. At the underground lake, the group hears a noise and use the night vision camera to discover the security guard with his eyes missing, whimpering in the shallows. The tall, humanoid creature appears, and slowly kills the guard by snapping his neck. Natasha's shocked gasp alerts the creature, and it chases the terrified group.

The creature attempts to seize Peter, but retreats from the camera light. In another room, the group discover a small pile of eyes and human flesh from previous victims. The main camera loses power, prompting Steve to replace the battery, when the creature lunges at the group. During the chaos, Natasha gets separated and runs off with the night-vision camera. The creature tracks down Natasha and seizes her, with the camera still recording as it drags her back to the lake. Steve and Peter follow the sounds back to the lake.

The creature begins to drown Natasha, but Steve and Peter chase it away with the main camera light. As Steve helps Natasha, Peter is heard in the distance screaming and challenging the monster, drawing it away. Peter emerges critically wounded, escaping with Steve and Natasha to a well-lit tunnel near a train station, as the event is captured on CCTV. Natasha borrows a cell phone to call the emergency services, breaking down and weeping as Peter dies.

The epilogue states that the coroner found Peter died from internal bleeding, Natasha resigned from her job as a journalist, Steve still works as a news cameraman, and Tangles' whereabouts remain unknown with his family still searching for answers. The police investigation was closed due to 'contradictory evidence'.