Joss Stone
Two men planned to kidnap and murder Joss Stone Reuters

Junior Bradshaw and Kevin Liverpool are on trial after planning to abduct and decapitate singer Joss Stone in June 2011.

The motive for kidnapping Stone remains unclear, and the suspects deny charges of plotting to rob and kill the 25-year-old.

The British singer shot to fame in 2003 when her debut album, “The Soul Sessions,” went multi-platinum. In 2007 Stone won a 2007 Grammy Award for Best R&B Performance by a Duo or Group with Vocals. She is the fifth richest British musician under 30, the Sunday Times reports.

Bradshaw, 32, and Liverpool, 35, reportedly planned to dump the singer’s body in a river after decapitating her.

Their goal was to kidnap her at her Devon home. They headed there armed with knives, a samurai sword, a hammer, gloves and bags, but never made it.

Neighbors saw the two driving around slowly, and called police after suspecting criminal activity.

In the first day of proceedings at Exeter Crown Court this week, prosecutor Simon Morgan told a jury that handwritten notes that allegedly revealed details about their plan were found in the defendants’ vehicle.

E! Online reports that some of the sections read, "Jocelyn RIP" and "Once Jocelyn's dead ... find a river to dump her."

Though the motive for the murder plot remains unknown, Morgan said some of the notes describe the suspects’ displeasure with Stone being invited to the 2011 wedding of Prince William and the Duchess of Cambridge.

The suspects may have sought a ransom or targeted Stone due to her ties to the royal family. The trial is still underway.