It happened sometime between 5.40pm and 6pm on Saturday 26 September at the Nuffield Health and Fitness facility on Hornbeam Park Drive, and involved the theft of a high value watch from a locker.
Email peter.henderson@northyorkshire.police.uk if you can help.
Alternatively, you can call North Yorkshire Police on 101, select option 2 and ask for Peter Henderson, or contact Crimestoppers anonymously on 0800 555 111 or via their website.
Please quote reference 12240176113 when passing on information.