Morbidology is a weekly true crime podcast created and hosted by Emily G. Thompson. Using investigative research combined with primary audio, Morbidology takes an in-depth look at true crime cases from all across the world.

Ken Allen was a Bornean orangutan living at the San Diego Zoo. He swiftly became the most famous animal in the history of the zoo due to the number of successful escapes from his enclosures he committed.

Ken was born in the zoo in 1971. According to some sources, he was given the name “Ken” after Alex Brown & Company, a Wall Street brokerage, gave the zoo a hefty donation and requested that their “ugliest” orangutan be names after one of the firm’s equity traders. Other sources claim he was named after zoo keeper, Ken Willingham, and zoo security officer, Ben Allen. Ken was raised in the zoo’s nursery after his mother, Maggie, made threatening gestures towards him.

Early on, it was evident that Ken suffered from an incurable wanderlust. While in nursery, Ken learned to escape his crib by removing the bolts. He also enjoyed unscrewing any light bulb he could get his hands on. From then until Ken got too large, JoAnn Thomas, one of the zoo’s nursery attendants, often took Ken out of his crib and took him around the zoo in a stroller. “He was like the precocious child who was just too intelligent for his own good,” she stated.

Ken’s first escape from his enclosure happened in June of 1985 when the 4 foot 6 inch, 250-pound, orangutan escaped by climbing up his retaining wall. During the escape, Ken – who had a very passive nature – just wandered around the zoo and looked at all of the other animals like any other patron of the zoo. In fact, Ken was so placid that a number of visitors walked right up to him and had their photograph taken with him.

The second escape came in July of 1985 and the third in August of 1985. However, during the final escape, Ken made his way to the enclosure of Otis, a Sumatran orangutan and former pen-mate of his who was “not known to be amiable.” Once there, Ken threw rocks at Otis before he was escorted back to his enclosure.

Ken Allen giving the finger to Reddit user, Dibble86.

Ken became such a celebrity that the zoo marketing department sold sweatshirts with his face emblazoned on the front with some witty slogan such as: “Free Ken Allen.” Moreover, a local artist recorded a song titled: “The Ballad of Ken Allen” in which he sung that Ken wag “smarter than a hundred humans at the San Diego Zoo.” He even had his own fan club known as the “Orang Gang.”

Ken wasn’t just known for his escapes, either. While he was typically placid, staff at the zoo said he despised when humans paid special attention to any of the other apes. On one occasions, a TV crew was filming the gorillas in the enclosure next door to Ken when he started lobbing rocks at them. When he ran out of rocks, he proceeded to throw faeces which sent the crew scattering.

The zoo spent $40,000 to completely secure this Houdini’s enclosure. They smoothed the front surfaces of the rock outcropping, eliminating any cracks and crevices used by Ken to pull himself up. Afterwards, Ken was never able to escape again. “He’s not cured, just contained,” said Ken’s keeper, Gale Foland. “I think the impulse to climb out is still there.”

In addition to securing his enclosure, the zoo also introduced four female orangutans into his enclosure. Ken hadn’t had any companionship in almost a year; he had lived with his son, Kellen, who had died of an internal infection that hadn’t been noticed by zoo staff until it was too late. “It’s so hard to tell when these animals are sick,” said Karen Killmar, animal care manager for primates. “It’s such an instinctual thing for them to hide it.” While the female company did keep Ken occupied somewhat, he taught some of them how to use a branch like a human would use a crowbar in an attempt to help them escape.

On the 1st of December, 2000, Ken Allen was euthanized after being diagnosed with advanced cancer. He was just 29-years-old; orangutans can often live well into their 40s and the oldest in captivity lived to 65. The decision to end Ken’s life was said to be a surprise to staff at the zoo who expected him to have at least six months left to live. “That’s the uncertainty of medicine,” said Bruce Rideout, the zoo’s chief of pathology. “Our chief concern was quality of life. Believe me, this took us by surprise.”