Mark down March 29, 2018 in your calendars because it's the day killer mermaids are heading to Freeform. The premiere date for Siren was announced at New York Comic-Con today, along with a chilling description of the series.

What if there was something sinister swimming beneath the sea's surface? In Freeform's next epic tale, Siren, the coastal town of Bristol Cove, known for its legend of once being home to mermaids, is turned upside down when a mysterious girl (Eline Powell) appears and begins wreaking havoc upon the small fishing town. Using their resources, marine biologists Ben (Alex Roe) and Maddie (Fola Evans-Akingbola) must work together to find out who and what drove this primal hunter of the deep sea to land, and are there more like her out there?

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It doesn't sound like she's the only mermaid who will hit Bristol Cove if the casting news also announced at Comic-Con bears and weight.

Aylya Marzoff and Sedale Threatt Jr. will both join the cast in recurring roles in Season 1. Marzoff will portray Katrina, an alpha leader of the mermaid colony, while Threatt Jr. will portray Levi, a warrior merman with an imposing presence.

Siren premieres with a special two-hour episode on Thursday, March 29th at 8/7c on Freeform.

SIREN - "On The Road" - What if there was something sinister swimming beneath the sea’s surface? In Freeform’s new original drama “Siren,” the coastal town of Bristol Cove, known for its legend of once being home to mermaids, is turned upside down when a mysterious girl (Eline Powell) appears and begins wreaking havoc upon the quaint village. Using their resources, marine biologists Ben (Alex Roe) and Maddie (Fola Evans-Akingbola) must work together to find out who and what drove this mermaid out of her home, and are there more like her out there? (Freeform/Jeff Weddell) ELINE POWELLSIREN - "On The Road" - What if there was something sinister swimming beneath the sea’s surface? In Freeform’s new original drama “Siren,” the coastal town of Bristol Cove, known for its legend of once being home to mermaids, is turned upside down when a mysterious girl (Eline Powell) appears and begins wreaking havoc upon the quaint village. Using their resources, marine biologists Ben (Alex Roe) and Maddie (Fola Evans-Akingbola) must work together to find out who and what drove this mermaid out of her home, and are there more like her out there? (Freeform/Jeff Weddell) ELINE POWELL