Matt Winkelmeyer/Getty; Karwai Tang/WireImage
Beckinsale, 48, shared a screenshot on Thanksgiving of a text message conversation in which she suggested to Sheen that she had posted a photo of her backside online.
In reality, Beckinsale sent her daughter, whom she shares with ex-boyfriend Michael Sheen, one of the various photos shared by Madonna, 63, the day prior.
"@lily_sheen had a fright," the Guilty Party star captioned her cheeky Instagram post, adding, "God bless @madonna 💕."
At the top of the screenshot, the photo of Madonna underneath a bed with her bare bum sticking out can be seen. Underneath, Beckinsale made it appear to Sheen as though she had posted the image herself.
"Do you think it's too much that I posted this," the Jolt actress asked her daughter. "The thing is my ass looks good."
"I'm a little confused I must say," a seemingly stunned Sheen replied to her mother. In a second text, Sheen added, "I do think it's a little much but it's also very arty."
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That's when Beckinsale decided to spill the beans. "Lol it's Madonna," the actress said in one text and "Like I'd ever" in another.
"I can't believe you can't recognise your own mothers anus from under the bed," she quipped in a third and final text.
The photo used in Beckinsale's prank was originally posted Wednesday by Madonna, who says Instagram subsequently removed them. On Thursday, the Grammy-winner reposted the steamy images, which show her posing on and around a large bed in black lingerie and fishnets.
In the caption, Madonna claimed the photos had been taken down because "a small portion" of her nipple had been "exposed."
"It is still astounding to me that we live in a culture that allows every inch of a woman's body to be shown except a nipple," the singer wrote in the caption. As if that is the only part of a woman's anatomy that could be sexualized. The nipple that nourishes the baby!"
"Can't a man's nipple be experienced as erotic ??!! And what about a woman's ass which is never censored anywhere," she added. "Giving thanks that I have managed to maintain my sanity through four decades of censorship…… sexism……ageism and misogyny."