Dateline: Secrets By The Bay - 5 harrowing details about Elizabeth Sullivan's disappearance and murder, explored

The disappearance of Elizabeth Sullivan back in 2014 shook up San Diego. She was a young mother who went missing, leaving everyone with questions about her whereabouts for two years. Elizabeth was married to Matthew Sullivan, an ex-Navy man, and had two kids. One day, she had an upsetting phone call with her best friend, Calandra Duckett, and then she was gone.

It wasn't until two years later that her body was found floating in San Diego Bay. This was right around the time her husband, Matthew, was getting ready to move to Maryland with his new girlfriend. In 2021, things took a serious turn when Matthew was found guilty of killing her. He was charged with second-degree murder and was sentenced to 16 years in prison.

Dateline: Secrets by the Bay talked to people close to Elizabeth Sullivan, played recordings of 911 calls, and showed evidence that no one had seen before. Here are 5 harrowing details about the murder:

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Details about the murder case of Elizabeth Sullivan

1) Elizabeth's final phone call

On the evening of October 13, 2014, Elizabeth Sullivan reached out to her best friend, Calandra Duckett, distressed and in a fight with her husband.

Duckett recounted while speaking to Dateline:

"She sounded frantic. They were arguing, and she said this [expletive] is talking about he’s gonna kill me."

Sadly, this was the last time Duckett would hear from Elizabeth Sullivan. Looking back, it served as an eerie premonition.

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2) Matthew Sullivan hid Elizabeth’s body for two years

Elizabeth Sullivan’s remains were discovered in San Diego Bay on October 6th, 2016, which was about two years after she went missing.

Prosecutors think that before her body was thrown there, it was probably hidden somewhere, like in a freezer. This all came to light on the day her husband, Matthew Sullivan, was moving out of the house they shared, which the authorities found strange and suspicious.

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3) The murder weapon was hidden in the attic

After Matthew Sullivan was taken into custody in early 2018, authorities decided to look around his place one more time. And that's when they stumbled upon something in the attic—a military knife with a blade that had Elizabeth Sullivan's blood on it and both their DNA all over the handle.

That was the moment everything changed in the investigation. Kim Collier, the detective working on the case, was moved when they found it.

She said,

"I actually cried when I found it. It was the moment we knew we had him."

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4) The disturbing 911 call

On the very day Elizabeth Sullivan went missing, Matthew placed a peculiar call to the emergency services, 911.

He spoke to the person who took the call, saying,

"Hi. I have concerns my wife is trying to … have me evicted or arrested from my house, and take my children away from me."

He mentioned that she used his credit card to hire a divorce lawyer. The investigators later figured out that the call was probably Matthew's way of spinning a false story about Elizabeth leaving her family behind.

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5) Matthew Sullivan's cold courtroom behavior

During his court case, Matthew Sullivan remained remarkably composed, rarely showing any feelings. He didn't seem sorry for what happened to his wife, Elizabeth Sullivan, and was more concerned with how he thought the trial was being run unfairly.

He said:

"The only issue I had about trial was I believe I was not allowed to call in relevant witnesses to my defense."

The judge and prosecutors called him out for not taking responsibility. They said,

"There is clearly no remorse from the defendant. He does not deserve probation."

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Dateline: Secrets by the Bay, about Elizabeth Sullivan, can be streamed on Peacock.

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