This Other Eden - S3.E5

Di Crabbe and DS Cambridge are assigned to investigate a spate of garden thefts carried out while the owners are away for a few days. It's not just a few plants that are being stolen - whole gardens are being stripped. The only person appearing to benefit is landscape designer Alan Wellbeloved, who becomes the prime suspect for the robberies. Returning home, Henry is horrified to discover that Margaret has hired Wellbeloved to redesign the restaurant's back garden to provide an outdoor dining area.