Ever since the hit Netflix documentary series "Tiger King" made quarantine more exciting for viewers, the mystery behind Carole Baskin's husband's sudden disappearance has become an interesting topic that leads to numerous conspiracy theories. 

Now, it looks like the "Big Cat Rescue" founder has admitted to the fact of wanting to kill her husband. But Carole Baskin does not talk about her missing second husband, Don Lewis, but rather her first husband, Michael Murdock. 

The 59-year-old animal activist allegedly said that she "would have eventually killed" Michael in a shocking letter she wrote 30 years ago. 

The 11-page letter, which was recently unearthed by TMZ, is Carole's message to on Lewis' first wife, Gladys, in August 1990. At the beginning of the letter, Carole appears to give out details during her 9-year affair with Don and pleads Gladys to help and forgive him. 

But it also revealed a disturbing line as Carole talks about her first husband, Michael Murdock. 

"Perhaps I asked for too much, but I had to get out of my marriage and would have eventually killed my husband to do it," Carole wrote. 

When asked to comment about the letter, Carole clarified that she only wrote it because she had lived an abusive marriage and would have acted in self-defense if given a chance. 

"I only meant it in the context of self-defense as Mike Murdock was physically abusive to me to the point of causing me to fear for my life," Carole told TMZ. 

The big cat-enthusiasts married Murdock in 1979 had a daughter named Jamie. They divorced in 1991 and then married Don in the same year.  

Despite the clarification, retired homicide investigator Jim Rathman finds the letter interesting as it was written seven years before Don's disappearance. 

Rathman leads the investigation on Lewis's case as part of the "Investigation Discovery" special entitled "Tigers, Lies, and Cover-Ups."

In one episode shown to the "Daily Mail," investigators brought a trained canine to sniff the waters nearby Lewis' lake house. The female dog appeared to be disturbed by the scent she picks up and starts whimpering and barking as the boat went to a portion of the lake. 

"There's something in that lake, there's something that's causing the dog to continuously alert on the west side of the lake near Don Lewis' house," one of the investigators said. 

Rathman said that cadaver dogs could detect human remains even if it is buried 20 feet below water. 

"The fact we have her alerting on the same spot was extremely exciting," Rathman said. 

"We are not going to find a body, but if Don, hypothetically, had gone through a meat grinder, we are looking for soft bone fragments, clothing, or maybe a tooth. Best case scenario is you find a tooth or bone that you extract DNA from," he added.

The revelations came before Carole Baskin was axed during the elimination night of "Dancing With the Stars." Carole danced to "The Lion King" complete with lion costume but failed to impress the judges leading her to be eliminated from the celebrity dance-off.  

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