Security footage shows who killed Missy Bevers. Three years on, no one has been caught.

It was the night of April 17, 2016, and the weather report for the following day called for rain.

But as ever, fitness instructor Missy Bevers was determined.

She posted to Facebook that the bootcamp fitness class she was due to teach the following morning would be going ahead, whatever the weather.

“If it’s raining, we’re still training,” she wrote.

Then she went to bed early – her class was at 5 a.m., and she needed to arrive early to set up for it.

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Missy entered Creekside Church, Midlothian, Texas, at 4:20 a.m. the following morning. But what she didn’t know was, someone was already inside waiting for her.

At 5 a.m., when members of her class arrived at the church, they found Missy ‘unconscious and unresponsive’ and bleeding from multiple puncture wounds to the head and chest, inflicted by an unknown implement. It was clear she had been the victim of a brutal attack.

Paramedics were called but it was too late – Missy died at the scene. She was 45 years old.

The small, tight-knit community of Midlothian was in shock.

Who would want to kill Missy? The vibrant former teacher was an active churchgoer and a beacon of the community.

She’d been married to her husband Brandon for 18 years and had three daughters, Hannah, 15, Allie, 13, and Sarah, nine.

She had no known enemies.

Could she have been the victim of a robbery gone wrong?

Police began a murder investigation, calling in help from the FBI and from Texas Rangers.

They started by checking the church’s surveillance cameras. The footage revealed that at 3:50 a.m., an unknown assailant had entered the building by breaking through the glass in a side door. The person was dressed in mock SWAT gear, all black with a riot-style helmet. There was no way to even tell if the suspect was a man or woman. The only distinguishing feature was his or her walk – they moved awkwardly, with an unusual gait, appearing to have an injury to their right foot or leg.

The videotape showed the suspect moving nonchalantly through the dimly-lit church, carrying a hammer. They opened and closed various doors and didn’t appear to be in any sort of hurry.

Further analysis estimated that the suspect stood somewhere between 157cm and 170cm tall, leading some to suspect it was a woman rather than a man.

Surveillance footage from outside the building also revealed a light-coloured 2010-2012 Nissan Altima driving through the carpark of a nearby sports store just hours before the murder, but police were unable to locate the vehicle or the driver.

Having discounted the robbery theory due to the fact that nothing was missing from the church, police started to dig into Missy's life.

It was two days before they were able to speak to Missy's husband, Brandon. He'd been 965km away on a fishing trip at the time of the murder, so was not considered a suspect. But police did uncover evidence that both Brandon and Missy had had extramarital affairs and that they were having financial troubles.

Brandon insisted that the couple was working through their problems.

They also found that just days before the murder, Missy had received a message from a man she didn't know on LinkedIn. She had shown the message to a friend, describing it as 'creepy' but the friend was unable to recall the name of the sender.

Police later found another set of messages Missy had exchanged with another man who they described only as "a person of interest". The messages were described as "flirtatious and familiar".

While Brandon had a solid alibi, attention turned to his father, Randy Bevers, with many observers pointing out he had a similar posture and gait to the suspect seen in the video.

There was also the fact that just 96 hours after Missy had been killed, Randy had taken some bloodied clothes to a local dry cleaner. He told police his dog had got into a fight with another dog, and that the blood was canine. Forensic tests confirmed this.

Randy also had a rock-solid alibi. Friends and flight information showed he was travelling in California at the time of the murder.

In late 2016, police confirmed that all members of the Bevers family had been cleared, including Brandon and Randy. They had also investigated nine different people who had had contact with Missy in the days before her murder and all of them had been ruled out as the killer.

In an interview with Fox4 KDFW, Brandon said he could forgive the individual responsible but only if he or she comes forward.

"We need closure," Brandon said. "This is going to eat us alive for many years to come."

Three years on, police appear to be no closer to serving the murder.

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