Tonight's episode opens up with a few drunk college kids playing with an ancient Egyptian book of the occult while partying in a crypt.  The foursome attempts to perform a spell that will open a door to an alternate universe.  If their glassy eyes and vacant expressions are any indication, it would appear the spell worked.  Each of them finds themselves in very different settings - a bloody torture dungeon, a room displaying dusty artifacts, etc - but each of them are alone ... oh, except for the creepy guy with a murderous stare hiding in the corner (William Mapother).  A scream from one of the girls brings them all back around to their senses.

Constantine, hard drinking by himself, gives a toast to an enchanted mirror that lets him "wallow in the past."  Manny pays him a visit to shake Constantine out of his isolation and give him a job.  Constantine heads to the local university to drop in on his old pal, and university instructor, Ritchie Simpson (Jeremy Davies).  While John is being his usual pain-in-the-ass self, one of the four students succumbs to the murderer lurking in the alternate dimension; the young man's death by suffocation in that world causes him to drop dead in this one without any obvious cause.

Back in Ritchie's office, the disgruntled teacher is none too pleased to be contacted by Constantine again.  Constantine's equally upset to hear that Ritchie is no longer monitoring the spikes in energy caused by the rising darkness.  If he still had his algorithm up and running, perhaps he'd notice that some of his students are seeing a transdimensional killer in their dorm room mirrors.  That's a hard sell since even the other members of the group don't seem to believe the young girl's story.

Simpson and Constantine, however, are more than happy to hear her version of the night's events.  John gets a lead on the cemetery-based origin of the supernatural events, along with a sniff or two that tells him Ritchie and his students are hiding something.  While on his investigation, Constantine is greeted by Manny once again.  It's a bit unusual to see the angel tagging along for the action, especially with Zed and Chas out of the picture for this episode.  Manny's interested in possibly getting Ritchie aligned with their side against the Rising Darkness, but he checks out again before too long.

There's some cool and creepy camera work and practical visual effects at play in the scene showing another of the students practicing her dance routine in a darkened studio as the killer blinks in and out of view in the floor-to-ceiling mirrors.  When she eventually pops back over to the alternate dimension, she's once again confronted by the helpful man who's managed to avoid getting killed, but also can't seem to get out of the death trap, due mostly to the fact that the killer has cut his hands off...

Constantine arrives back at Ritchie's office (though he's basically taking it over) to ask him why his students were attempting to perform a ritual about traveling into alternate dimensions.  Ritchie discovers that the very relevant dream-walking journal of a scholar named Jacob Shaw has gone missing from his collection.  Legend has it that although Shaw was able to successfully perform the ritual, things invariably went rather wrong and his consciousness was trapped in the other dimension.

Back at the dorm, Adam and his girlfriend Lily are worried about their missing friend Miranda.  Adam wants to head back to the graveyard while Lily, who knows Miranda better, is headed to the gym.  They're on separate paths but with the same goal as Ritchie and Constantine, who are enjoying a moonlit walk across campus and engaging in a lively discussion of the singularity, among other things.  One of those other things?  The overwhelming presence of the rising darkness, which drove Ritchie to quit monitoring it.

Adam transports his consciousness to the other world and finds Miranda stabbed and bleeding; Lily finds the same thing in her own world.  Constantine and Ritchie find Adam in his altered state, just as the killer, ie Jacob Shaw, finds Adam in his world.  The madman slashes Adam to ribbons, and Constantine and Ritchie watch helplessly as blood pours from the young man's wounds.  By the next morning, Adam and Miranda are dead and Ritchie is blaming himself.  John tries to shake him out of it, but Ritchie knows his friend's full of hot air.  Ritchie thinks he's gotten just a taste of the guilt and shame that Constantine himself feels every day.

John and Ritchie do their best to save Lily, who tells them about "that house."  Cut to Shaw's murderous home in the other world where Carter, Adam, and Miranda are somehow still alive (even as the throat-cut Adam pulls a blade from Miranda's stomach).  Shaw goes on a villainous monologue, explaining how he plans to hunt the trio for sport.  Miranda and Carter run off, but Adam stands up to the nightmarish man, to his own detriment.

Constantine brings Ritchie and Lily back to his protective abode, free of the reflective surfaces that trigger the transport into the other dimension.  Free of mirrors, but not free of the reflective glass of cellphones.  Before they can stop her, Lily looks at her phone and comes face to face with Shaw.  She flees, only to find that the house exists in a limitless void of Shaw's own creation.  There is no (conventional) escape.  Good thing Constantine's anything but conventional.

They plan to hop to the other side, into Shaw's creation, with the hopes of not only finding each other but helping Lily get out alive.  Ritchie's worried going into Shaw's world without any spiritual guidance; luckily Manny chooses that particular time to appear, which bolsters Constantine's confidence as they trip into the nightmare house.  They manage to not only find each other, but pick their way through the house itself thanks to Ritchie's superior intellectual and imaginative abilities.  They soon find the helpful man that tried to assist the students, who turns out to be not so helpful after all: it's Shaw himself.

Shaw shows no remorse in killing the students who stepped into his world.  Ritchie calls him on his psychopathic behavior, but Shaw slashes his wrists and pins Constantine to the wall.  John attempts to convince Ritchie that he's just as strong a creative force in this world.  His friend's confidence in him works, and Ritchie conjures a beautiful, sun-soaked world that burns Shaw out of his bleak, pained existence.  While they manage to rescue the still very much alive Lily from the house, the rest of it collapses behind them.  Shaw and the others are gone.

Lily wakes up to rejoin the living world, but John and Ritchie remain in the construct.  Ritchie wants to stay behind in his own reality, basically as a God, so who can blame him?  Constantine can.  He warns his friend that he's eventually going to go as crazy as Shaw, and that his decision isn't about creating his own world, it's about running away from the real one.  Having regained consciousness, John pleads with Ritchie, still in his altered state, to come back to him ... which he does after a few moments of hesitation.  Having found new purpose, Ritchie puts more effort into his teaching position, lecturing about humanity's certainty of suffering, giving into cravings, and the possibility of inner peace.

Like all of Constantine's episodes this season, "A Whole World Out There" had moments of sheer beauty, earned by struggling through dark and often gruesome conflicts.  Ritchie's defeat of Shaw was born of will and creativity rather than strength of arms or knowledge of the occult.  Then, rather than devolve into an "everything's okay now" approach to closing out the episode, the writers took that opportunity to engage in a brief but thoughtful consideration on the incredibly complex balance of vice and virtue.  These moments are the rare gems of Constantine, the fleeting glimpses of a thing that could be greater if given enough time.

My only gripe is that, while the show handles its episodic nature fairly well, too little momentum and attention has been given to progressing the season-long storyline of the looming battle for Earth's legions of souls.  Unfortunately, it's looking like Constantine won't quite grant a definitive answer to the "rising darkness" in the next two episodes, and as it's still up in the air whether we'll get a season two or not, these final hours might be all we'll ever get.  If you haven't been making noise about Constantine up to this point, now's the time to start. #SaveConstantine

Rating: ★★★ Good — Proceed with cautious optimism

(An explanation of our ratings system follows here.)

Miscellanea:

Constantine: "Ya know, even God rested." Manny: "God rested because he was finished creating the world."

Simpson: "You gaze at the chaos long enough, it'll swallow you whole."

Constantine to a vanished Manny: "I'm not exactly a guiding light, now am I...ah, bollocks. You bloody get on my nerves sometimes."

Constantine: "Looks like Alice has already slipped through the looking glass."

Shaw: "I've always been a sportsman. That's what we do here; we play. So run along. You have free reign. Just remember that I'll find you."

Constantine: "Just like back in the day, huh?" Ritchie: "Yeah, a bit too much like it."

Ritchie: "Some God you turned out to be, Shaw.  You forgot the sun."

Ritchie: "All this time you've been here, you coulda been building worlds. You coulda been redefining life and how we live it. Instead you gave into your weakness, and when you did, that's the day you became obsolete."

Ritchie to John: "At least, in this world, I can forget about the darkness closing in on us, John."