Philly’s Penrose are rock dudes who are in deep with the blues. But not, you know, “my baby left me and I…” blues or the “I got the insert-mundane-problem-here blues.”They dig more into the existential roots of blues music; the struggles between good and evil, the balancing act of human existence. Stuff that traces from The Black Keys to Nick Cave and all the way back to Robert Johnson.

The three brothers who make up the band (Tom, Dan and Pat Murphy) are schooled not only in playing, but also vibe – those humming Hammond organs! that spooky Theremin! On their latest record, Circe – self released today and being celebrated this Saturday at Underground Arts – they harness that vibe to trace a themeatic arc. On the band’s 2011 debut Devil’s Grip, the Murphy brothers seemed like they circled around the border of the dark side. On Circe, they dive into the abyss.

“Every River Goes To Hell” strikes out on a rumbling chord arpeggio, tracing the journey through amp stacks, pounding drums and broken promises: “That ship is going down.” Death plays strongly into “Life of Mud,” the snappy, piano-led single we showcased yesterday. The mud in question is the earth that the deceased narrator is telling his tale from: “I know I won’t have a single regret, only these memories I ought to forget.”

The snarling, sneaky acoustic ballad “Tango With Lucy” is about a meeting with a seductive woman in New Orleans – who might just be the devil a total blues motif if there was one. “I wonder if she is who she says she is, but in this case, ignorance is bliss.” But there’s not a sight of redemption, or hope, just an acknowledgement of the often flawed side of human nature.

All these contradictions and complications are summed up in “Underground,” which might just be songwriter Dan Murphy’s manifesto. In the nearly seven-minute song, he knocks down icons of 20th century literature and philosophy: Joyce, Kafka, Bukowski. “God only knows what god only knows, you try to justify it with your lyrics and prose. / You tell your self things to help yourself sleep ’cause you just can’t imagine taking that leap.”

After traveling this train of thought, writing off religion, technology, science, dabblings with drugs and love and lust as a “highly praised way of twiddling your thumbs.” What’s the conclusion? No matter how much we know, or think we know, we don’t really know that much – we’re just idling away our time until it’s no longer there. HEAVY.

Or a dark reality check that’s made somewhat more palatable by heavy, rocking arrangements and even snappy moments. Which is the most exciting thing about Circe, and about Penrose. They play blues and rock in a loud and accessible way, but they don’t compromise when it comes to the themes. These guys are dark, unflinching, unafraid, and taking all those into consideration, more honest and clearheaded than most of their indie-blues peers.

Circe is the featured album in this edition of Unlocked; hear the spotlighted single “Life of Mud” in yesterday’s post, and check back later in the week for interviews, video and more.