CHICAGO -- "Empire" actor and R&B singer Jussie Smollett told Chicago police last month that two men physically attacked him and yelled racial and homophobic slurs. There have been dozens of twists and turns since then. Here are some key moments from the start of this story:Jan. 22Letter threatening Smollett arrives at the Chicago studio for "Empire"Jan. 29Smollett tells Chicago police he was physically attacked by two men in downtown Chicago while out getting food from a Subway restaurant at 2 a.m. The black and openly gay actor tells authorities the men used racial and homophobic slurs, wrapped a rope around his neck and poured an "unknown substance" on him. Police say Smollett told detectives that the attackers yelled he was in "MAGA country," an apparent reference to President Donald Trump's "Make America Great Again" campaign slogan that some critics of Trump have decried as racist and discriminatory.WATCH: Jussie Smollett interview with "Good Morning America": 'I am not weak'Jan. 30Chicago police say they've reviewed hundreds of hours of surveillance camera footage, including of Smollett walking downtown, but none of the videos show the attack. Police obtain and release images of two people they would like to question.Reports of Smollett's attack draw outrage and support on social media, including from U.S. Sen. Kamala Harris of California, U.S. Rep. Bobby Rush of Chicago and TV talk show host Ellen DeGeneres.Jan. 31Trump tells reporters at the White House that he saw a story the night before about Smollett and that, "It doesn't get worse, as far as I'm concerned."Smollett's family issues a statement calling the attack a racial and homophobic hate crime. Smollett's family says he "has told the police everything" and "his story has never changed," disputing assertions leveled on social media that he has been less than cooperative and changed his story.Feb. 1Smollett issues a statement telling people that he is OK and thanking them for their support. He says he is working with authorities and has been "100 percent factual and consistent on every level."WATCH: 'Empire' actor Jussie Smollett was hesitant to report attack, police report saysFeb. 2Smollett gives a concert in West Hollywood, California, opening with an emotional speech, saying he had to play the show because he couldn't let his attackers win.WATCH: Bottle that smelled like bleach found near Smollett attack locationFeb. 12Chicago police say Smollett turned over some, but not all, of the phone records detectives requested as part of their investigation. Police say the heavily redacted files aren't sufficient. Smollett says he redacted information to protect the privacy of contacts and people not relevant to the attack.Feb. 13Chicago police pick up two Nigerian brothers at Chicago's O'Hare Airport on their return from Nigeria after police learned at least one worked on "Empire." They questioned them and searched their apartment.A law enforcement official also told ABC News that the homes of the men were raided Wednesday night. Police removed shoes, electronic devices and other items they believe could help them determine if the two people played any role in the assault.Feb. 14Chicago detectives say the two are the "persons of interest" from surveillance video.Chicago police say reports that the attack against Smollett was a hoax are unconfirmed.Producers of "Empire" dispute media reports that Smollett's character was being written off the show.RELATED: 'Empire' actor Jussie Smollett was hesitant to report attack, Chicago police incident report saysFeb. 15Chicago police say Friday morning the two men are considered suspects.Friday evening, Chicago police release the two Nigerian brothers without charges, saying they have new evidence to check out as a result of questioning them. They give no details of the new evidence.Feb. 16Chicago police say the investigation has "shifted" after their interrogation of the brothers and they are "eager" to speak to Smollett again.Smollett's lawyers issue a statement saying that there is no truth to reports that he played a role in his own attack and that he feels "victimized."Feb. 17Chicago police say they're still seeking a follow-up interview with Smollett after receiving new information that "shifted" their investigation of a reported attack on the "Empire" actor. Guglielimi says police reached out to Smollett's attorney, but says an interview has not been conducted.Guglielimi declines to address reports that a grand jury may hear evidence in the case. "We're not confirming, denying or commenting on anything until we can talk to him and we can corroborate some information that we've gotten," he says.Feb. 19Chicago police say they're investigating a tip that on the night Smollett reported being attacked, he was seen in an elevator of his apartment building with the two brothers who were later arrested and released from custody in the probe. CPD later deemed the tip "unfounded."Cook County State's Attorney Kim Foxx's office announces she has recused herself from the investigation surrounding the alleged attack. First Assistant State's Attorney Joseph Magats is named the acting state's attorney in the matter.The brothers meet with prosecutors and police at the Leighton Criminal Court Building.Feb. 20Chicago police announce that Smollett is officially classified as a suspect in a criminal investigation for filing a false police report. He is charged with felony disorderly conduct.Feb. 21Smollett turns himself in to Chicago police about 5 a.m.Chicago police say during a press conference at 9 a.m. that Smollett paid the brothers $3,500 to stage the attack because he was "dissatisfied with his salary."Smollett appeared in court, where his bond was set at $100,000.Smollett posts bond and is released from custody.Feb. 22"Empire" showrunners announce that Smollett's character will be written off the last two episodes of the season.March 7The Chicago Police Department opens an internal investigation into leaks in the Smollett investigation.March 8A Cook County grand jury returns a 16-count felony indictment against Smollett.March 26Prosecutors abruptly dropped all charges against Smollett. His attorneys said his record had "been wiped clean" of the 16 felony counts related to making a false report that he was assaulted by two men. The actor insisted that he had "been truthful and consistent on every single level since day one."It was not immediately clear what prompted the decision to dismiss the case. Typically, a minimum condition of dropping cases is some acceptance of responsibility. The Cook County State's Attorney's Office said in a statement that Smollett agreed to forfeit his bond. He paid $10,000 in bail to get out of jail after his arrest. Among the unanswered questions was whether prosecutors still believe Smollett concocted the attack and whether new evidence emerged that altered their view of events.Chicago Mayor Rahm Emanuel called the dropping of charges against Smollett "a whitewash of justice" when he and Chicago Police Superintendent Eddie Johnson responded to the latest development in the case on Tuesday.WLS-TV contributed to this report.