In Horace Takes a Hand, Carlo Costino ran a Dartmoor "escape" club to which Dartmoor prisoners were encouraged to subscribe. Prisoners who escaped would make their way to a pre-arranged hideout on Dartmoor equipped with civilian clothes, food and weapons. In this way, they could avoid using public roads and could lie low until such time as it became safe to evacuate them by air overseas.
Carlo co-owned a Soho nightclub with his brother Luigi Costino. Both had been sent to Dartmoor for peddling dangerous drugs. Carlo had a shorter sentence and came out first and set up his escape club. He bought an Auster (registration G-AOSL) which he housed at a club in Somerset and then delivered parcels of supplies to a dell-hole in Dartmoor which he had chosen for the hideout.
Unfortunately for Carlo, his preparations had been spotted by fifteen year old Horace Wilburton, who reported his observations to Biggles. A month later, Luigi Costino escaped from Dartmoor and made his way to the hideout onlyto find the police waiting. Carlo arrived in his Auster two days later to pick Luigi up and was also arrested. Luigi believed his brother had tricked him and told police the whole story. Both Carlo and Luigi returned to prison.