More than 50 drain covers were stolen from streets in Clackmannanshire and Stirling over 24 hours.
The bizarre thefts took place between noon on Thursday March 25 and noon on March 26.
The 51 cast iron metal gulley covers were taken from Menstrie Place, Brook Street, Elmbank Street, Abercrombie Place, Windsor Street, all in Menstrie, Fort Street in Cambus, Dollarbeg in Dollar and Smithfield Loan in Alloa.
They were also removed from the Hillfoots Road in Stirling between the Logie Kirk roundabout to the innovation park.
The drain covers are often stolen for resale as scrap metal. Thieves have previously targeted manhole covers and sections of railway track in the same area.
A Central Scotland Police spokeswoman said: "A total of 51 gulley covers were taken from these streets and a vehicle would have been needed to remove them.
"We appeal for anyone who saw anything suspicious to contact us."
Anyone with information can contact Central Scotland Police on 01786 456000 or information can be given anonymously to Crimestoppers on 0800 555111.