Jack Donald Lewis (born April 30, 1938) was an American missing person who disappeared on the morning of August 18, 1997, after leaving his home in Tampa, Florida.

No evidence has surfaced that Lewis was the victim of a crime, but friends, family, and investigators believe it is unlikely that he disappeared by choice because he had been executing business plans that were left unfinished.

Lewis's disappearance was covered in both seasons of the crime documentary series Tiger King, which focused on a feud between Baskin and Oklahoma-based private zoo owner Joe Exotic.

[11] According to Murdock, who remarried in 2004 and took the name Baskin, Lewis was obsessed with sex and would frequently fly to Costa Rica to engage in affairs – especially when she was menstruating.

[1] In the days leading up to his disappearance, he had bought a plane ticket to Costa Rica and was loading equipment onto a truck he planned to drive to Miami.

[11] In July 1997, Lewis filed for a restraining order against Baskin, claiming she had threatened to kill him and had hidden his gun to prevent him from protecting himself; the request was rejected.

[2] The Hillsborough County Sheriff's Office "found no sign of foul play" at the Tampa sanctuary and visited the Costa Rican town of Bagaces, where Lewis owned a 200-acre (81-hectare) park, as part of their investigation.

[1] In Costa Rica, investigators found indications that Lewis engaged in extramarital affairs and questionable business practices.

In a statement to The Tampa Bay Times, the manager said that she had done so under Lewis's specific instructions, that the insurance policy had several additional beneficiaries, and that she had also helped him transfer property to others.

[3] In March 2020, using the popularity of the Netflix documentary series Tiger King, Hillsborough County Sheriff Chad Chronister appealed to the public for legitimate leads or evidence for the case.

[14] Chronister expressed his belief that a former employee of Wildlife on Easy Street that had a sour relationship with either Lewis or Baskin will step forward with evidence.

[17][18] In December 1998, Pam Lambert of People magazine wrote that there was "a wealth of suspects and scenarios, but precious little evidence" in Lewis's disappearance.

[20] After the first season of Tiger King was released, several Internet memes targeted Baskin for her speculated involvement in Lewis's disappearance.