Project Beast was revealed at the Sony E3 press conference this evening by Sony Worldwide boss Sony's Shuhei Yoshida. The game is titled Bloodborne, which was trademarked recently.
It's being directed by Hidetaka Miyazaki, who did Demon's Souls and Dark Souls 1.
Not much else is known at this time, but Sony said to expect to hear more on the game soon.
Bloodborne is set for release in 2015 on PS4.