Boston (CNN) -- Over eight days of testimony, jurors in the trial of reputed mob boss James "Whitey" Bulger have seen tears from witnesses whose loved ones died in bloody gangland shootings, heard horror stories from victims who barely survived drive-by shootouts, and peered into the world of the mob through testimony from an old friend turned star government witness.
And things are just warming up -- the trial, which is expected to take up to three months, enters just its third week on Monday.
Bulger is charged in the deaths of 19 people during some two decades when prosecutors say he ran Boston's Irish mob. He also faces charges of extortion, racketeering and money laundering.
After escaping a 1995 indictment, allegedly on a tip from a rogue FBI agent, Bulger went into hiding for 16 years, landing himself on the FBI's most wanted list before getting arrested with his girlfriend in Santa Monica California in 2011.
Among highlights from the first two weeks of testimony:
-- In three days on the witness stand, former Bulger associate and hitman John Martorano casually detailed killing after killing, confirming to prosecutors that together he and Bulger were involved in 11 slayings, two of which put Bulger on the firing end of a gun in a killing. Bulger had admitted to another two murders he'd committed on his own, Martorano testified.
-- A callous Martorano showed brief signs of emotion, telling the jury that when he found out Bulger was an FBI informant, "It broke my heart. It broke all loyalties." Martorano testified that he thought Bulger's FBI confidant, John Connolly, was just doing a favor to Bulger's well-respected politician brother by looking out for "Whitey" and the gang. He knew the crew was going to benefit from tips from inside the FBI, but he never though Bulger would become a "Judas" or "a person like an informant, a rat, a no good guy," which in "Southie" -- south Boston -- was the ultimate sin.
-- Defense attorneys and prosecutors were at each others' legal throats all week, taking jab after jab while court was in session. In one spat, defense attorney Hank Brennan accused Martorano of being a liar in front of the jury, turning the room into a vacuum of tension. Prosecuting attorney Fred Wyshak fired off an objection before U.S. District Court Judge Denise Casper put the kibosh on the ugly squabble with, "That's for the jury to decide."
-- Two jurors were reduced to tears as one witness, 63-year-old Diane Sussman de Tennen, alternated between bouts of crying and attempts to smile as she recounted the night she was in a car that suddenly was riddled by bullets, leaving her then-boyfriend a quadriplegic for the remaining three decades of his life. She was riding in a car that Martorano and Bulger rained fire on in March on 1973, mistaking the driver with another gang-rival target, according to Martorano's earlier testimony. Jurors heard gripping testimony from three people who barely survived drive-by shootings, and seven family members of victims who died in alleged mob killings.
-- Famed "Godfather" actor Robert Duvall was an unlikely spectator in the federal courtroom Friday morning. Duvall is expected to play a federal judge in an upcoming movie called "The Judge." A smiling Duvall became immediately stern when court was called into session, paying aggressive attention to Judge Casper. He sat with his hands propped on his knees, and listened intently to the testimony, methodically turning his head back and forth.
Bulger sat through all eight days of it, mostly expressionless except for one notable moment.
His former bookmaker, Richard O'Brien, was on the witness stand describing a meeting between Bulger and a man who owed him money.
When the man balked at paying, O'Brien said, Bulger told him, "We have a business besides bookmaking."
"What's that?" the man asked.
"Killing (expletive) like you," O'Brien quoted Bulger as saying.
The 83-year old defendant threw his head back and let out a laugh.
On Monday, the prosecution intends to introduce Bulger's full informant file, a 700-page document detailing his relationship with the FBI over 15 years.
Jurors also will hear from former FBI Supervisor John Morris, who gained immunity after agreeing to testify about cash he accepted from Bulger in exchange for protecting the mobster from the law. Tensions in the courtroom are likely to be high in anticipation of a Morris-Bulger face-off.
The jury will continue to hear from family members of alleged murder victims, law enforcement operatives from Bulger's past, and at least one more of his former associates in a trial that could last well into August.