It is likely that Penelope Cruz will act in 'Pirates 4' i.e.'Pirates of the Caribbean: On Stranger Tides'. It is not yet clear which character she will play. Both Orlando Bloom and Keira Knightley has decided not to act in this fourth edition of 'Pirates'. So, it is not clear whether Penelope will play the character played by Keira.
This film is set to release around May, 2011.