Deputies Surprise 7-Year-Old Boy Suffering from Terminal Illness with 'Thriller' Dance

Deputies from the Pasco Sheriff's Office raced Spencer Holt to a disused jail where he battled a group of zombies before officers performed Thriller.

A seven-year-old boy suffering from a terminal illness got to experience Halloween early - and a day he'll never forget - thanks to some generous Florida officers.

Deputies from the Pasco Sheriff's Office raced Spencer Holt to a disused jail where he battled a group of zombies with a NERF gun before watching uniformed officers perform an epic Thriller routine.

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Speaking to INSIDE EDITION, Spencer's mom Cher explained that he was first diagnosed with mitochondrial disease in 2012. It causes seizures and digestive problems and leaves him sapped of energy, she said. He spends much of his time in hospital.

Knowing that the boy is a fan of the Walking Dead, deputies helped create a drama-filled day to get his mind off his hospital stays. They picked up the youngster from school in a police car last Tuesday, put on the light and headed to the jail.

"He lit right up," Cher said. "He felt like he was famous."

Spencer thought he was visiting the jail to meet with sheriff's deputies, but when he arrived, a member of a SWAT team rushed in and him they needed his help fighting zombies. Fifty drama students from two nearby high schools stepped into the roles of the zombies - growling and trying to grab the boy as he shot at them with his toy weapon.

"He couldn't believe what was going on," his mom said. "He was smiling the whole time."

But that wasn't the end of the surprise. After he saved the county, Spencer was led into another room - where the uniformed deputies began dancing to Michael Jackson's Thriller.

Cher, who had no idea they were going to perform the routine, said she was so touched by their show of support.

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"Everybody hears all the bad news [involving the police] but everyone needs to hear this," she said. "They took time out of their day and some were off duty. It was so special that they were doing this on their day off."

For Spencer, it was a great break from hospital visits, his mom said. He has been ill for most of his life and can sometimes suffer from seizures that leave him unresponsive for upto 17 hours.

"He's got worse," she said. "We see bad days and we see good days. Now he's getting older, he's getting upset he's in the hospital. We try to make it as happy as possible."

And that's exactly what the officers helped them do, she said.

"There's no words to describe how thankful I am. They are forever in my heart for what they did. I'm speechless," she said, adding: "Spencer keeps asking when he can do it again."

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