Police are searching for a man who stole cash from a kind-hearted Bicester householder on Thursday last week.
Officers have asked any witnesses to come forward after the burglary in Brashfield Road, off Buckingham Road, at just before 8pm.
A man, who the victim recognised as a tree surgeon who had carried out work for him previously, had asked the householder to change a £20 note for two £10 notes.
Due to the fact he recognised him, the homeowner let the man into his home and took out his wallet to change the cash.
But as he opened his wallet, the crook tried to grab it.
The homeowner managed to hold onto his wallet but the thief was still able to snatch a quantity of cash before running off.
The thief got into a dark-coloured car parked in Buckingham Road, and drove off in the direction of Buckingham.
PC Kirsty Morris, of Bicester Police Station, said officers investigating the theft were keen to hear from anyone in the area who had been offered tree surgery work on their gardens.
The thief is described as a heavily-built white man, about 40 years old, around 6ft tall and with a large stomach.
Anyone with information regarding the theft is asked to contact PC Morris at Bicester Police Station via the Thames Valley Police Enquiry Centre on 101.
Details can also be left with the Crimestoppers charity anonymously on 0800 555111 or online at www.crimestoppers-uk.org.
Thames Valley Police is inviting Bicester residents to sign up for up-to-date local crime and safety messages through the www.thamesvalleyalert.co.uk service.