Agent Knox may no longer be a part of the investigation into Nucky in the upcoming episode of Boardwalk Empire.

In a new promo for the episode The North Star,Agent Knox (Brian Geraghty) has lost the confidence of J. Edgar Hoover (Eric Ladin), after his botched attempt to kidnap Eddie Kessler (Anthony Laciura) and turning him into a confidential informant. In Erlkonig, Kessler protected not only his estranged sons, but gangster Nucky Thompson (Steve Buscemi), by jumping out of a window and committing suicide.

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In the promo clip, Knox's abilities to investigate Nucky are questioned.

"An informant is dead. The operation is compromised," Hoover says to Knox.

"Give me one more chance," Knox says.

His newest target may be Eli (Shea Whigham).

According to Cartermatt.com, this isn't the only drama that will unfold in the new episode.

Nucky will reunite with Margaret (Kelly Macdonald) in New York City before heading back down to Tampa to work out the details of his new land deal with Bill McCoy (Pearce Bunting). While there, he will also reconnect with Sally Wheet (Patricia Arquette).

Also in Tampa, Meyer Lansky (Anatol Yusef) continues to go on his own land deal alone, after potential partner Lucky Luciano (Vincent Piazza) gets scared out of it by the New York connected Vincenzo Petrucelli (Vincenzo Amato).

Meanwhile, back in Atlantic City, Richard Harrow (Jack Huston) will be making a confession to Paul Sagorsky (Mark Borkowsky), before returning to Julia (Wrenn Schmidt).

Boardwalk Empire airs Sundays at 9:00 p.m. on HBO.

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