What deal did Charles II make with Louis XIV of France?

In the Secret Treaty of Dover Charles II agreed to help Louis against the Dutch, with whom he was officially allied, and conquer the protestant country. The only people present at first were the two kings and Charles' sister Henrietta. Louis also paid Charles a pension, which made him less dependent on parliament.

Since the Netherlands were protestants and France was catholic, many English thought of it as betrayal when they found out.