A mum had just sat down for breakfast when she saw a deadly scorpion scuttle across her kitchen floor.
Carol Cook, 51, from Stansted, Essex, let out a scream when the three inch arthropod reared up as though to sting her.
Carol's husband Gary, 51, came to her rescue, scooping up the scorpion in a glass, before seeking advice from the local council's environmental health department.
Card merchandiser Carol said: "When I saw him I was jumping around screaming and so was my daughter, Billie, but Gary stepped up to deal with it.
"He's the one in house who deals with spiders - it's always been his job since we married. He was quite calm considering what was going on - a lot calmer than me, that's for sure.
"I've seen the movie The Scorpion King so I know what they are capable of."
The family returned from a three week trip to Australia at the end of September and Carol suspects the unwelcome visitor may have hitched a ride in one of their suitcases. Meaning he has been hiding out in their home for over three months.
"It creeps me out to think he has been with us for all that time," Carol adds.
Wildlife experts have identified the invader as a lethal American bark scorpion – whose sting is powerful enough to kill children and elderly people.
They are usually found in Florida and Arizona but Iain Newby, who runs the Dangerous Wild Animal Rescue Facility, says that he doesn't rule out the suitcase stowaway theory as people travelling the world every day made such occurrences very plausible.
"Everyone travels the world, somebody from America could have gone to Australia," he said. "Then Mrs Cook comes back to the UK with her new friend - a scorpion can hide in a little tiny two-inch pocket in a briefcase and you would not even know it was there.
"They curl up and they hide, like spiders."
Mr Newby warned that for children under five years old, and people aged over 70, the scorpion's sting could kill you.
"If you are fit and healthy, it is going to hurt like bugger, he added. "It would be like 50 bee stings - you may not die but the hurt is going to hurt. I would not mess around with it at all.
"It might even be gravid and it might give birth to live young."
The family have now nicknamed the scorpion the 'Beast of Stansted' and it is currently living in their home, safely secured in a plastic takeaway tub (with air holes punctured through the lid) until a suitable home can be found - which for Carol can't come soon enough
"I have certainly not got friendly with him and he won't be staying here for much longer," she said.
"My friends have been saying I must be mad to keep it in the house - especially as they often live in pairs, so I am hoping this one was a loner."