On a two-month hiatus, the last eight episodes are to premiere on June 13, 2019.
- More and more merfolk are suddenly appearing on land, having been forced out. This further increases the dangers of the imminent discovery of their existence. Katrina and Levi return with four others; one of whom is Donna's own daughter. With the assistance and discretion of one-eighth mermaid Helen Hawkins, Ben Pownall and Maddie Bishop hide the pack of mermaids and mermen in the old cottage of Ben's parents Ted and Elaine, which has been inactive for ten years.
- Having already beaten Katrina in combat, Ryn is now the leader of her colony, and the others willingly turn to her for help and guidance; all except Katrina who considers her "weak" like humans.
- To further escalate matters, Xander McClure is still furiously vengeful towards Levi for murdering his father, and falls for a seemingly kind black-haired teenage girl named Nicole, who is, in fact, secretly working for the military to further their search in capturing more merfolk for further experiments.
- Meanwhile, Maddie's drug-addict mother Susan suddenly returns to Bristol Cove after eight long months in the hope of making things right with her daughter, and Helen eventually discovers more crucial information about her mermaid heritage.
- When the existence of merpeople is ultimately revealed to the public, some work together with said merfolk to put a stop to the oil rig that prevents them from returning home to the sea. However, this alliance has devastating results, leaving an uncertain future for both races.
- The Arrival
- The Wolf at the Door
- Natural Order
- Oil and Water
- Primal Instincts
- Distress Call
- No North Star
- All In
- Mixed Signals
- Filming for Season 2 begins on July 26, 2018 and is scheduled to end on March 15, 2019.
- At San Diego Comic Con 2018, it was stated that Season 2 would further explore the Siren Song and how it impacts male human characters. At the same panel, it was revealed that more mermaids and mermen are set to appear in Season 2.
- A four-month hiatus is said to come, as the first two episodes of Marvel's Cloak & Dagger second season is airing on April 4, 2019, at 8 pm. The last eight episodes will begin airing on June 13, 2019.
- ↑ Disney ABC Press—"Breaking News From Freeform’s 2018 Upfront Presentation" (May 15, 2018)
- ↑ TV Line—"Siren Season 2 Gets January Premiere Date, Bloody Teaser Trailer — Watch" (October 4, 2018)
- ↑ SpoilerTV—"Production Dates - Various Shows *Updated 16th June 2018*" (June 16, 2018)
- ↑ Siren - SDCC Panel News