There are some places in this world where you just don't expect to see any rude stuff – one such place being a wildlife-preservation group's Twitter feed.
And when The Woking Peregrine Project tweeted a picture earlier this week, advertising their appearance on The One Show last night, it all seemed very innocent on the surface.However, eagle-eyed followers soon noticed something rather amiss about the photo.
And we have to say that we found it rather shocking (and highly amusing), too...
The snap featured three members of a filming crew, along with their video camera, in a nondescript car park – nothing wrong with that, you might think.
But if you studied the picture closely – and some people clearly did – you could see something decidedly filthy.
A shadow cast by the man in the middle's head on the bloke on the right's shirt resembled... well, we can't really say it here. You'll have to take a look for yourself.
Oh my! I hadn't noticed that before, and now it can't be unseen!
Blissfully ignorant to the lewd image they'd created, project member Craig Denford wrote: "Tune into The One Show this evening to see the Woking Peregrines featured. 7.00pm. BBC1."
But followers on Twitter weren't about to let them get away with their mishap in a hurry.
One sniggered: "This will go down in history as a whoops moment!"
Another added: "And the explanation of the shadow on the guy on the right's shirt!!"
And a third exclaimed: "Oh my! I hadn't noticed that before, and now it can't be unseen!"
Eventually, the group did notice the saucy silhouette, but they seemed to take it in their stride.
Tweeted Denford: "The shadow has already become an internet celebrity in its own right!"
Thankfully, the group's appearance on The One Show went off without incident.