Update 23:14 - Here is a synopsis for the season
In the wake of the burning of Charles Town, all the New World lives in fear of Captain Flint. But when his campaign of terror crosses over into madness, it falls to John Silver to locate the man within the monster before it’s too late. Meanwhile, with Eleanor Guthrie in prison, Jack Rackham oversees a new Nassau, hoping to secure his legacy as a king among thieves. All will be tested when a new threat arrives, one the pirates could never have anticipated. It knows them. It understands them. And in the blink of an eye, it will turn them against each other.
Source:
Thanks LesIconesDeFranck and RD for the heads up
Source: IGN