CANTON, Ohio — An Ohio man who initially said his wife died of natural causes during their trip to Graceland in Memphis pleaded guilty Monday to aggravated murder and gross abuse of a corpse in her death.

Seventy-three-year-old Philip Snider, of Hartville, Ohio, pleaded guilty Monday. A plea agreement calls for him to disclose where he put 70-year-old Roberta Snider’s body. In return, prosecutors have agreed to recommend a sentence of 20 years to life in prison.

The guilty plea is the latest chapter in a bizarre story and investigation across two states that prosecutors in Ohio detailed in a lengthy statement.

Snider told family members he took his wife to Graceland “one last time before she died.” Philip Snider said his wife passed away in Memphis, so he pulled over into a parking lot where he saw an EMS vehicle and asked for help. He claimed the paramedics confirmed she was dead, then took her to an unknown location.

In January, Snider told police his wife died of natural causes on the trip, emergency workers took her body and she was cremated.

Police in Ohio said they obtained video evidence from the hotel where Philip Snider stayed during his trip, and it was apparent that Roberta Snider was not with him during his hotel stay.

He later changed his story, saying his wife had actually passed away from her cancer somewhere in Kentucky. Instead of stopping, he reportedly continued the journey to Memphis.

On the way home, authorities said Snider wrapped his wife’s body in plastic and dumped her in the Tennessee River along I-40. He told police she died of natural causes and he had “put her with nature.”

Authorities searched the Tennessee River but couldn’t find the body.

Hartville, Ohio police said they had video evidence of Snider at a gas station in Wayne County, Tenn. that showed his wife was not in the cab of the vehicle with him. Before they could confront him with that evidence, however, police said relatives found Snider in his basement attempting to commit suicide by taking medication and placing a bag over his head.

He was admitted to a hospital.

Later, police used a cadaver dog to search Snider’s condominium. Inside a plastic bin, police said, the dog found a piece of a sweatshirt stained with human blood that matched Roberta Snider.

“At this point, Snider told authorities a third story,” Stark County, Ohio prosecuting attorney John D. Ferrero said in a statement. “This time, he stated that Roberta had died at their home in Hartville and that there was no ‘foul play.’ He stated that he had placed her body inside plastic trash bags, placed her in the bed of his truck, and drove to Memphis. Then, on the way home, he put Roberta’s body in the Tennessee river.”

After Snider was released from the hospital, police used a female undercover officer to befriend him over meetings at fast food restaurants in the area. The officer told Snider she was in town to care for her dying mother, and was having thoughts about killing her.

“After a few weeks, Snider discussed with the officer how the undercover officer could kill her mother without attracting suspicion,” Ferrero said. “The two also began discussing scenarios which surrounded Roberta Snider’s death.”

According to Ferrero, Snider proposed marrying the officer, so that when he died, she could collect his pension. The officer, however, told Snider that if they were to continue their relationship, he would need to be completely honest with her about what had happened to Roberta.

Ferrero detailed Snider’s story to the officer:

“Snider told the undercover officer that during the evening of January 2, he had a fight with Roberta, and she ended up sleeping on a love seat in the living room of their home. He awoke the next morning and went to Burger King for coffee and returned home a short time later. When he returned home, he went to the living room where Roberta remained sleeping. Her head was resting on two decorative throw pillows. Snider took a shop cloth, gently placed it over Roberta’s head, stuck her twice in the head with a two pound stake hammer, killing her. He then tied a plastic grocery bag over her head and rolled Roberta’s body onto a plastic tarp adjacent to the couch. He stated that blood splattered on the two decorative pillows and on a lamp near her body.

“Snider parked his pickup truck inside his attached garage and closed the garage door. He placed Roberta’s body into a Rubbermaid container with wheels and took the body upstairs to the garage. There he put plastic garbage bags over the body and loaded it and the container into the truck. He loaded the plastic, stake hammer, pillows, lamp, and the shop cloth into various Rubbermaid containers and also loaded them into his truck. He then disposed of the evidence, including Roberta’s body, at various locations between Hartville and Memphis.”