The Lady in Red
The day after the robbery a man known as Jimmy Lawrence met his girlfriend, Polly Hamilton, for a date. He had been seeing her for two weeks. She was renting out a room from a Romanian immigrant named Anna Sage. Sage was currently facing deportation proceedings, stemming from her convictions resulting from charges related to her running brothels in Gary, Indiana, and East Chicago. Only Sage knew that Jimmy Lawrence, was in fact, John Dillinger. While living quietly in his new identity, the manhunt was continuing. Hoover had appointed Samuel Cowley to head up the investigation in Chicago.
On July 20, 1934, Anna Sage contacted acquaintance Martin Zarkovich, an East Chicago police sergeant, and offered to reveal the whereabouts of John Dillinger in return for both the reward money and help in blocking her deportation. Zarkovich contacted Melvin Purvis. At subsequent secret meeting with Purvis and Cowley she outlined her offer and received assurance that they would help with her deportation problem. She told them that she would be going with John and Polly to the movies at the Marbro the following evening.
On July 22, all available agents were briefed on the setup. At 5:30 p.m., Sage called and confirmed that they would attend a movie that night at either the Marbro, or the Biograph theater. Secondary plans were quickly made to have Purvis and Agent Ralph Brown stake out the Biograph. Spotting Dillinger and the women arrive at the Biograph, where Manhattan Melodrama featuring Clark Gable was showing, Agent Brown immediately called Cowley. Agents quickly surrounded the theater. Purvis was stationed left of the entrance.