As you've likely already been reminded by Google or morning television, today is Earth Day, a worldwide observance designed to demonstrate support for environmental protection. To celebrate the 44th annual event, Dark Horse is offering a special digital deal on an ecological cautionary tale: The Massive.

Written by Brian Wood and illustrated by a roster of artists that's included Kristian Donaldson, Garry Brown, Gary Erskine, Declan Shalvey and Danijel Zezelj, The Massive follows direct-action environmentalists in the wake of a crippling global ecological disaster as they sail the oceans aboard the Kapital in search of their lost sister ship the Massive, coming up against pirates, thieves and murderers as they try to survive in a post-apocalyptic world.

If you've not checked out the series, today is your chance: Dark Horse is making the first four digital issues available for free. If you want more, or if you're already a fan but fell behind on your reading, the publisher has an offer for you, too: all 22 digital issues for just $10.

It's a one-day deal, so take advantage of it while you can. And think of the trees you're saving!