6 p.m., National Aquarium, 501 E. Pratt St., (410) 576-3800, mermaidskiss.org, $95 for individual ticket, $170 for pair.
Bad news: Our oyster supply is in danger. This is a problem because oysters help filter the Chesapeake Bay’s water and because, you know, oysters are delicious. Support the Oyster Recovery Partnership by enjoying drinks, live music, after-hours access to the Aquarium’s exhibits, and endless raw oysters—and yes, eating oysters does help save oyster reefs because their shells can be recycled to produce baby oysters. Win-win.