Maybe you missed both of Goose Island's 25th-anniversary parties in May. Maybe you haven't seen their excellent 25th-anniversary ESB, which was distributed so thoroughly that I was able to pick up a six-pack at the Dominick's two blocks from my apartment. But anyway, yes, Goose Island turns 25 this year. And the Clybourn brewpub (which operates independently of AB-InBev) is getting in on the action by hand bottling a series of small-batch beers. Two months ago it released the first, a fine double APA called Silver Jubilee, and on Friday it bottled Cthulhu—an imperial oatmeal stout aged in an 18-year Elijah Craig bourbon barrel. Both beers use the same generic 25th-anniversary 750-milliliter bottles, but Silver Jubilee is capped with dark green wax, Cthulhu with copper.

Cthulhu goes on sale when the brewpub opens today at 11 AM; bottles are $20 each, with a limit of one per person. (Silver Jubilee is still available for $10.) Many thanks to manager Lisa Carlson and brewmaster Nick Barron for hooking me up with a complimentary bottle of Cthulhu on Saturday so I could review it in advance.

Cthulhu is of course the best-known—one might almost say the best-loved—of the ancient, extradimensional abominations that H.P. Lovecraft called the Great Old Ones. (Those of you who are somehow unfamiliar should read the short story "The Call of Cthulhu," published in 1928.) And the Elijah Craig 18-year won "best bourbon" (and a double gold medal) at the San Francisco World Spirits Competition in 2010, though I'm taking the Internet's word for that—I can find only 2013 results on the competition's website.

I couldn't tell you what connection exists between the two in the minds of the good Goose Island folks—maybe they're suggesting that this beer, having already aged in a barrel used to mature an exceptionally old bourbon, will take well to cellaring? As Lovecraft's "Mad Arab," Abdul Alhazred, famously put it, "That is not dead which can eternal lie. And with strange aeons even death may die." At any rate, the name got my attention.

Cthulhu the beer thankfully does not possess "a stench as of a thousand opened graves," though its aroma does fill the room once you've poured it—I can smell it distinctly even when my glass is sitting four feet away. Bourbon, cocoa, vanilla, and coconut come forward most aggressively, backed by a tiny bit of boozy sting—the beer is 10 percent alcohol, and it could pass for stronger if you weren't allowed to taste it. I'm persuaded that the aroma also includes notes of baked raisin, toffee, and that wonderful but doubtless murderously unhealthy species of pecan praline that's dark, buttery, and meltingly soft. Your results may vary, especially if you aren't trying to write an entire blog post about this beer.

Cthulhu tastes much like it smells, except even more chocolatey—I'm getting fudge and baker's chocolate, plus espresso, bourbon bread pudding, and a touch of black cherry. It's only very subtly carbonated, but the whiskey and charred oak from the barrel give it a mild, tongue-tingling astringency.

Considering its strength, the beer is surprisingly, pleasantly light, more silky and creamy than syrupy—I'm reminded of Central Waters' great bourbon-barrel stout. ("Syrupy" is the one complaint I've heard about Goose Island's famous Bourbon County Brand Stout that I think really sticks. Pun intended!) Cthulhu has a long aftertaste full of vanilla, but it doesn't leave a film on your teeth.

I was spoiled for choice when it came to the metal portion of this Beer and Metal post—as you might imagine, more than a few such bands have taken inspiration from Lovecraft. But I'm gonna go straight down the middle and post Metallica's "The Call of Ktulu," the instrumental that closes 1984's classic Ride the Lightning. This is a fan-made video using clips from the H.P. Lovecraft Historical Society's 47-minute silent film of "The Call of Cthulhu," released in 2005 after two years in production (and quite an impressive piece of work considering its minuscule budget).

French ambient black-metal band the Great Old Ones named their 2012 debut album Al Azif (according to Lovecraft, the original title of the Necronomicon), and its second track is called "Visions of R'lyeh," a reference to the sunken city in the south Pacific where Cthulhu is imprisoned. They also do a barely recognizable cover of Bjork's "Bachelorette."

Philip Montoro writes about beer and metal, singly or in combination, every Monday.