For the past few years, networks have been digitally inserting ads and product placements for new products into old reruns. Shannon just noticed one in a rerun of a 2007 episode of “How I Met Your Mother.” In the background on the shelf is a magazine with an ad on the back for the new “Zookeeper” starring Kevin James. Here’s the original shot, which shows no books on the back shelf.

So does this mean Robin is buying bootleg DVD’s? Or there’s an unrevealed storyline where she’s a movie reviewer for the local paper, seeing advance versions of the latest films? It raises all sorts of questions about timeline and continuity, and the more you stare at it and try to figure it out, the more the brand burns itself into your brain.

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