In Detroit, a young girl has been left without a mother, and nagging questions continue to linger about what really happened to her.

It's been four years since Tamala Wells disappeared, and Detroit Police have been working to connect the dots ever since. Why did Wells vanish? Who is responsible?

His name is Rickey Tennant. Tamala Wells knew him as her boyfriend. The Detroit couple had a baby girl together who is now 10 years old and living with her dad.

Tennant has never been arrested or charged with any crime in connection to Tamala's disappearance. He seemed eager to talk about a cloud of suspicion that hangs heavy over him, even allowing Crime Watch Daily into the home he once shared with Tamala.

Rickey and Tamala's twisted tale of denials and mystery all started early in the morning of August 6 with a phone call to Florida.

"I answered the phone I could hear a scary voice of a little girl saying 'Grandma, my mama didn't come home last night,'" said Donna Wells, Tamala's mother.

Donna Wells received the frantic call from her then-6-year-old granddaughter Navia.

Back in Detroit, many days later, cops receive a call too, from Rickey Tennant.

"He reported the vehicle gone and he then found it himself, and before calling us," said Detroit Police Sgt. Marcellus Ball.

Tennant reports that his girlfriend Tamala is missing, telling police the last time he saw her she was driving his car on the way to hang out with friends. A few days later, with no sign of Tamala, Tennant claims he heard from a friend named "Bud" who apparently spotted the car abandoned and parked across town.

"Well, I knew I had a jack and a basketball in the trunk and it wasn't in there, I had it in the trunk and it wasn't in there, and I called my sister and somebody up, and I called the police up 'cause I didn't want to mess with the car," said Tennant.

But detectives say Tennant did mess with the car -- so much so that any potential evidence was wiped out.

"Instead of calling us to come to the scene to investigate, Mr. Tennant took it upon himself to go inside the vehicle, to search the vehicle, and that's when he called us. And that was very odd and disturbing to me," said Sgt. Ball.

Donna Wells found other actions odd and disturbing. She wasn't able to get Tennant on the phone for six days after her daughter went missing. Frantic, she flew to Detroit in a desperate search for Tamala.

Was Rickey Tennant ever considered a suspect?

"Yes," said Sgt. Ball. "Everything leads us back to Mr. Tennant in some kind of way, That's not something that normally happens, but in this case it is."

Cops bring Tennant in for questioning, and he agrees to a polygraph test, which detectives say he flunked.

"Probably because I'm mad inside about all the things I'm hearing about, she done did," said Tennant. "But If I did something wrong or whatnot, I wouldn't have taken a lie-detector test. But I know I ain't did s--- to nobody."

Tennant claims he only took one polygraph test. Sgt. Ball says he took two and failed them both.

"He got so agitated to the point where we thought that he was going to attack the polygraph examiner," said Ball. "That's not the behavior of someone who was innocent."

As the mystery deepens with murky details and few leads, the case goes as cold as a Detroit winter.

"We're still investigating," said Sgt. Ball. "Just because you believe something to be true you have to prove it beyond a reasonable doubt, and right now we can't do that."

Now Donna Wells and Rickey Tennant are locked in a bitter battle over the truth behind Tamala Wells' whereabouts.

And four years since her beloved daughter vanished, Donna Wells refuses to give up. She continues to canvass the area, handing out flyers.

Rickey Tennant does have a message for his missing girlfriend: "Tamala, if you out there would you please come home? I want you to see your daughter Navia. She's 10 years old going on 11, would you please come home if you out there?

"Whoever trying to put this on me, you all on a bunch of crap, 'cause Rickey ain't did nothing," said Tennant.

If you have information related to the disappearance of Tamala Wells, contact Detroit Police, or submit a tip to Crime Watch Daily. You can remain anonymous.