Staff were threatened with a gun during an armed robbery in Stone on Friday night.
At about 9.50pm, a man wearing dark coloured clothes entered the Co-op store in Oxford Road and threatened the staff as he demanded they hand over any money.
The man is around 6ft 2ins and skinny.
After taking the money he ran off in the direction of Stone.
Det Sgt Nick Hind, leading the investigation, said: “The man threatened the staff with, what we believe at this stage, to be a gun.
“I would urge anyone who witnessed the robbery and has not yet spoken to a police officer or was in the area at the time and saw the man before or after the actual robbery took place, to come forward.”
Anyone with information which could help the police should contact the police via 101, or if you don’t want to talk to the police or give your name, call the Crimestoppers charity on 0800 555 111.