Old Shame: The time Det. Miller fell for a gang member while undercover, resulting in Veronica's conception.
Recycled Script: S3's "Beautiful Little Fool" was remade in practice as S4's "Torn". Both begin with a young woman bringing the case of a long deceased relative, a young woman that was murdered. Both are the team's new record for oldest case reopened, the only case in the series from that decade, and take place in the last year of said decade ("BLF"'s victim is a 1929 flapper, "Torn"'s is a 1919 socialite). In both cases, the clue that solves the crime is provided by an old woman, who was a little girl when the murder was committed, and is the only witness still alive, with every other testimony being provided by books, records, diaries, historians of the era or descendants of the people involved. The perp is long deceased in both (as it could only be realistically) but left a recorded confession. The murder was committed during the arrival of a big historical event that destroyed the fortune of a man related to the victim (a member of the Vanderbilt family that lost his fortune in the Crash of 1929 in "BLF", a beer magnate that went out of business with Prohibition in "Torn").