Jack's back and ready to fight the good fight once again against those dastardly terrorists. It's another very, very, very long bad day for the Counter Terrorist Unit of Los Angeles as some key characters are targeted for assassination, prompting Jack to come out of hiding. This time the terrorists have access to some very unpleasant nerve gas and they may be working with someone within the government administration. To say much more about individual episodes would risk giving too much away, suffice to say there are shocks galore and even in it's fifth outing this series is likely to give you more heart palpitations than you could shake a stick at.