DALLAS — Deanna Cook lived her life in fear of her ex-husband.
In a 911 tape, she can be heard saying, “I have a stalker."
She was afraid that even calling police would get her killed, but she called again and again.
COOK: "I don't want him to know I even called. You know what I'm saying? That's the thing. That triggers him when he knows I called. He tears the stuff up in my house.”
OPERATOR: “We'll tell them, but they're still going to contact you."
Cook called 911 repeatedly in the weeks and months leading up to her death with the same concerns.
In another call, she said her ex was watching her house.
COOK: "He's already tried to kill me three times. I'm really just fed up with this. I can't keep moving and changing my life because of this [expletive].”
The operator tells her to document police calls and get a restraining order. Cook is frustrated, afraid and tired.
COOK: “I've been going through this for five years with him. It's still the same thing. I have complaints. If you look up my name, you'll see there are a hundred thousand complaints, but ain't nobody doing nothing."
OPERATOR: "When was the last time you called police?”
COOK: “Umm, two weeks ago, and they just tell me not to open my door. And all that."
The operator ended that call with a final piece of advice.
OPERATOR: “All I can do is try to help you. It's up to you to do the things that we suggest to you. But if you don't do that, police hands are tied."
Cook's final 911 call came on August 17, 2012.
OPERATOR: “Dallas 911, this is [unintelligible]. What's your emergency?”
That call was answered at 10:55 that morning.
OPERATOR: “What's your address?”
In her final call, Cook never speaks directly to the operator, but over the next nine-and-a-half minutes, she is heard pleading with her attacker and begging for her life.
About three minutes into that call, a voice believed to be her ex-husband asks her if she called police.
COOK: “I'm not doing nothing to you."
It's during this time the police call sheet shows that the operator is searching for Cook's address; she had called from her cell phone.
As the operator searches, Cook's frantic pleas can be heard.
COOK: “Please, Red! I didn't do nothing! I’m nice. I'm nice. Please!"
Delvecchio Patrick responded, ordering Cook to kneel down and then adding that he's going to kill her.
By 11:04 a.m. — nine minutes after the call started — the operator found the address and updated the computer entry, labeling it "urgent."
But it was too late.
Within 20 seconds, there's a final plea from Cook, and the man she called "Red" answered with a final threat saying that he was going to kill her.
At 11:04:25, the call goes silent.
Police finally arrived at Cook's home 51 minutes after she called. They knocked on the door, No one answered, and they left.
Cook's family discovered her body two days later.
On the day Deanna Cook was killed, the Dallas 911 call center had a handful of operators on duty and no supervisors helping with difficult calls.
Also her call was never upgraded to top priority, so officers took their time.
The operator on that final call was suspended for 10 days, but ended up resigning.
This case has forced Dallas police to take a hard look at their 911 center and make operational changes.
WFAA -- KENS 5's sister station in Dallas -- obtained recordings of three 911 calls made by Deanna Cook — two made in the weeks prior to her death and a third that recorded her murder.
The final call is too gruesome to publish, but the other converstations reveal Cook's frustration and exasperation in an effort to find safety from her ex-husband.