Jimmy begins a rogue investigation into D’Angelo Barksdale’s death, suspecting it wasn't a suicide.
Omar continues hitting Barksdale stash houses.
If you are looking for a "guide" to the actual music video for the song, it is often treated as a short cinematic piece.
It depicts 50 Cent training in a high-tech lab (the "Shady/Aftermath" center) before entering a stylized club environment.
This episode is titled "Familiar-Like" but is widely referred to by fans as the "In Da Club" episode because the primary plot centers on the characters attempting to get into an exclusive nightclub.