Happy International Mermaid Day 2018! It's time to celebrate all things fishy and fabulous, and that can only mean one thing ... watching the two-hour premiere of Siren tonight at 8/7c! (Psst! Click here to see where you can watch Freeform!) If you want to catch up on all things Siren, you can check out our cast page and see all our latest news right here, but for now, we want to see just how ready you are for the most mesmerizing holiday around. Take our quiz below.