It appeared in mid-November, and by Thanksgiving weekend it had vanished. The mysterious metallic monolith with more than a passing resemblance to a certain iconic object from one of the greatest sci-fi films ever made brought a little X-Files flair to an otherwise grim news cycle. But now that it’s left us, we’re still wondering: Whodunnit?
You can say aliens, or inter-dimensional beings, or prankster artists, or just full-on pranksters for that matter. But what if...what if that enigmatic slab, which was installed illegally according to the officially unamused Bureau of Land Management, was actually a viral advertisement for a movie, TV show, or some other celebrity-endorsed endeavor?
io9's Jill Pantozzi thinks Justice League could be to blame. What are your weirdest theories?
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