Zack Morris forked out £2.80 on a sandwich so he could "cheese slap" Tilly Keeper and Jasmine Armfield while they were asleep.
The sneaky "EastEnders" star - who plays Keegan Baker on the BBC One soap - splashed out on the lunch item before removing the cheese and playfully whacking it upon his fellow Albert Square residents as they were catching 40 winks.
Tilly - who plays Louise Mitchell - wrote on Twitter: "i still actually cannot believe @_zack_morris paid £2.80 for a ham and cheese sandwich just so he could cheese slap me and @jasarmfield whilst we were napping (sic)"
Zack - who has been nominated for Best Actor at the upcoming British Soap Awards - admitted his sarnie purchase was well worth the expense.
He tweeted: "And it was worth every penny (sic)"
Tilly and Jasmine (Bex Fowler) may want to watch out the next time they are napping because their co-star Davood Ghadami (Kush Kazemi) has vowed to put some money towards a whole block of cheese.
He wrote: "Well worth the money. Next time I will chip in for a slab of cheese... (sic)"
Shona McGarty (Whitney Dean) was also in on the act and couldn't stop laughing when Zack pounced on the unsuspecting pair.
She tweeted: "I'm sorry.... I am to blame too. But tbf, if was funny af. X love you both. X x. Xx. X x (sic)"
A cheese slap tends to see someone taking a piece of plastic cheese before wetting it and slapping it on someone's face, usually when they are sleeping.