The two sadistic kidnappers/torturers/rapists are based on Leonard Lake and Charles Ng, two men who met in the military who captured, tortured, raped and murdered numerous women and murdered entire families to steal their IDs, money, and cars.
This is the first episode in which Detectives John Munch and Odafin Tutuola are the primary detectives on a case rather than Benson and Stabler.
Like Daryl Kern, Charles Ng was arrested in Canada for shoplifting, and also fought extradition on the grounds that he would be executed in the US. Ng finally lost his case, and was extradited to the United States. Unlike the Law & Order story, it was the dominant personality - Leonard Lake - who was arrested first. Lake committed suicide with a cyanide capsule. In 1998, Ng was convicted in California of 11 counts of murder and sentenced to death. He remains on death row awaiting execution.
This marks the first time in the series (or any other series in the Law & Order franchise) that the detectives travel outside of the United States, as Munch, Fin and ADA Alexandra Cabot travel to Canada. It happens again in season four's Pandora (2003) when Detective Stabler travels to Prague, Czech Republic and a third time occurs in season nineteen's Gone Fishin' (2017), when Fin travels to Havana, Cuba.
When Munch and Fin are at their motel in Walden Falls and talking about their time on the job, Fin tells Munch that he transferred out of Narcotics because his partner took a bullet meant for him. This incident would not be explored until twelve seasons later in the Season 14 episode, Poisoned Motive