A month ahead of Swamp Thing's premiere, DC Universe has released the first full trailer for its next original live-action series. Definitely leaning harder into the horror genre than the streaming service's other shows, the trailer shows something lurking in the swamp that may be friend or foe while revealing much of the upcoming show's extensive cast of characters.

Here's a quick rundown of the DCU's haunting trailer and the faces that appear throughout it.

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Strange Happenings in the Swamp

The trailer opens with a swamp boat making its way deep into the bayou late at night with what appears to be an unwilling passenger. As the boat drifts to a stop, the men piloting it hear an ominous growling in the distance.

As they search for whatever appears to be stalking them, they are dragged screaming into the water around them by plant-like tendrils creeping into the boat from the swamp itself. Later, a young girl is seen falling into convulsions at her school and horrified to discover what appears to be her father stabbing something in his bedroom upon her return home. While none of these characters are likely to be big players in the series, and may not even be given names, their reactions here set the stage for Swamp Thing's bayou-fueled horror.

Meet the Cables

As supernatural occurrences begin to escalate around the swamp and the small town in Louisiana, Sheriff Lucilla Cable and her lawman son Matt are seen investigating, guns drawn and flashlights ready.

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Portrayed by Jennifer Beals and Henderson Wade, respectively, Matt had been series' protagonist's Abigail Arcane's boyfriend in high school before she left for college and got a job with the CDC. In the comics, Matt was a government agent married to Abby for a time before their marriage dissolved and he took a turn for the supernatural with John Constantine.

Abby Arcane

Swamp Thing with Abby

The character with the most screentime in the trailer is Crystal Reed's Abigail Arcane. One particularly chilling sequence in the trailer has Swamp Thing rise from a gurney behind her and drag her screaming through her lab with his tendrils.

The DCU incarnation of Abby is a CDC scientist who returns to her hometown to develop a cure for an unseen epidemic from rare plants and elements found in the swamp with the trailer briefly showing her co-worker Harlan Edwards, portrayed by Leonardo Nam. In the comics, Abby is Swamp Thing's primary love interest who develops her own extraordinary abilities while her father is the villainous Anton Arcane.

The Sunderland Corporation

Glimpsed briefly is Virginia Madsen's Maria Sunderland, a woman intrigued by the supernatural mysteries of the swamp after losing her daughter. Her husband is Avery Sunderland, portrayed by Will Patton, the head of the conglomerate Sunderland Corporation with his own plans for the swamp's mystical potential.

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n the comics, the Sunderland Corporation had long hunted Swamp Thing, hoping to learn all sorts of mysteries from the plant-based superhero for their own profit and nefarious ends. Given the character descriptions for the Sunderlands in the DCU series, this antagonistic relationship is likely to continue in live-action.

The Floronic Man

John Glover as Jason Woodrue in Batman & Robin

One of the scientists seen studying pieces of Swamp Thing in his lab is Kevin Durand's Jason Woodrue. A biogeneticist studying the swamp for his own sinister agenda, the trailer teases the character's transformation into the environmental villain the Floronic Man.

Originally an obscure DC Comics character, Alan Moore had revived the character for his acclaimed Swamp Thing run as a mystical, elementally powered figure that would rival Alec Holland and reveal earth-shattering news about Holland's own monstrous transformation.

Blue Devil

Ian Ziering's Daniel Cassidy is seen briefly in the trailer, reflecting on his glory days as a stuntman long gone by. Performing death-defying stunts as the Blue Devil, Cassidy's blue, horned helmet worn by his namesake is glimpsed in a chest with other relics from the stuntman's career.

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In the source material, Blue Devil is a former stuntman turned supernatural superhero after he's accidentally transformed into his Hollywood namesake by the demon Nebiros who confuses him for a fellow monster. Imbued with magical, superhuman abilities, Blue Devil fights occult evil throughout the DCU.

Madam Xanadu

One of the last major characters seen in the trailer is Jeryl Prescott as Madam Xanadu. The fortuneteller is seen falling to ground, likely overwhelmed by some sort of supernatural vision that almost certainly portends a coming evil from the swamp.

The DC Comics version of Xanadu is a mystic with Arthurian roots who serves as a fortune and consultant of sorts to the other heroes of the DCU for all things supernatural and mystical. Blinded by the Spectre as part of his war against magic, Xanadu joins Blue Devil and the other magical heroes of the DCU as part of the team Shadowpact.

Executive produced by James Wan, Mark Verheiden, Gary Dauberman, Michael Clear and Len Wiseman, Swamp Thing premieres May 31 on DC Universe. The supernatural horror series stars Crystal Reed, Andy Bean, Derek Mears, Jennifer Beals, Henderson Wade, Will Patton, Virginia Madsen, Jeryl Prescott, Henderson Wade and Kevin Durand.