Marvel have the Color Your Own trademarked line of black-and-white colouring-in comics. IDW is launching a Locke & Key colouring-in book. The comic book industry is waking up to the adult colouring-in craze right now.

And in January, DC Comics will launch a themed variant line of black and white covers, not the usual "black-and-white" variety, but ones drawn intended to be coloured in by the buyers.

I wonder how many people will actually colour them in?

More from the Baltimore Diamond Retailer Summit right here.

UPDATE: Heidi has a shot of one of the covers by Dave Johnson…

Adult coloring books@covers in January. Here's the one by @Devilpig666 . pic.twitter.com/tH45Rki8I0 — Heidi MacDonald (@Comixace) September 25, 2015