Virgin Voyages has unveiled that entrepreneur Richard Branson will be joining the Valiant Lady’s MerMaiden voyage later this month, according to a press release.

The Valiant Lady will set sail for its Halloween-themed voyage on October 30 from Miami and the sailing will last for six nights, according to Virgin Voyages.

Guests onboard will be able to witness and participate in the breaking of a Guinness World Record as they gather to form the world’s largest mer-folk gathering.

To that end, the company is organizing a Shore Thing event in which attendees will receive a mermaid tail, a digital photo, bragging rights, a certificate, and access to an exclusive cocktail party. The number of guests is limited to 500.

Guests can join even without booking the Shore Thing experience, as long as they bring their own mermaid tail onboard to be part of the event.

The Scarlet Fright Night, the largest sea-monster bash at sea, as well as exclusive experiences and commemorative gifts for guests, will be featured on the Halloween-themed cruise. “Sailors” will also have the opportunity to enter a competition and win a free future voyage with the cruise line.