Five Go to Billycock Hill is the sixteenth novel in the Famous Five series by Enid Blyton.

The Five are camping on Billycock Hill, near the farm of Toby, a boy who loves jokes and pranks.

When Toby's cousin Jeff, a Royal Air Force pilot, and Jeff’s friend Ray are reported to have defected and stolen the newest aeroplanes, the Five and Toby are shocked.

The media later reports that Jeff and Ray crashed their planes and drowned at sea.

Later that day, Toby's younger brother Benny's pet piglet, Curly, appears with a message that leads the children to find Jeff and Ray imprisoned in Billycock Caves, who they rescue.