July 4, 1930.  40,000 horse racing fans fill Arlington Park.  Ness and his men have Arnold ""Spats"" Vincent under surveillance; they will close in on him as soon as he gets a piece of paper: a list with the names of officials in high places who are ready to do business with the crime cartel.  2 hoods (one tall, one short), apparently associates of Spats, approach him.  The tall hood sits next to him and whispers something to him; then he stabs Spats.  The hoods take off running; Ness and his men and some cops chase them. They arrest the tall hood, but the short one gets shot by a cop. Ness figures that top gangster Nate Stryker had put a contract on Spats; Ness and his men grill the tall hood, but he's not talking, he won't even give his name.  Ness has Stryker hauled in, but the tall hood won't squeal on him.  Later, Stryker meets with Dexter Lloyd Bayless-- he runs a school where he trains assassins; Bayless had provided the 2 hoods for this hit.  Stryker is worried the hood might si (thetvdb.com)