I guess it's Jack's great empathic ability that makes him the powerful performer that he is, but empathy comes at a price like all things-when he's surrounded by mediocrity he instinctively lowers the standard and becomes one with it. He is a joke as a mafia-hit-man(also because the part doesn't suit him one bit, him being so extroverted)and just grazing avoids making a fool of himself in this.Kathleen Turner had a much tooooo long career just by being tall and blonde, because her acting ability is limited to that thing she does with her eyes, when she opens them wide which she's convinced is sooooo damn sexy and Anjelica Huston is the absolute same(granted interesting) in everything, just like Robert Loggia.
The movie is a lame draft(and this will be the only mention of the rag they call script) of a gangster-movie, with a cast that was probably only interested to get to the after-party faster(they certainly gathered the party-going elite in this). What, did they shoot it in 1 day?-cause that would be the only explanation.