"The Untouchables" had many great elements:
1. An excellent cast, including several familiar faces from TV and films: Tom Amandes ("Everwood"), William Forsythe ("John Doe," "UC: Undercover," "Out for Justice"), John Rhys-Davies ("The Lord of the Rings," "Raiders of the Lost Ark"), and David James Elliott ("JAG").
2. Some entertaining -- if historically unrealistic -- stories, combining gangster action stories with looks into the personal lives of the characters, especially the relationships with Al Capone (Forsythe) and Eliot Ness (Amandes) and their respective wives and children.
3. Fantastic theme music by Joel Goldsmith (I'm still humming it, and I haven't seen the show in 10 years). I wish they had released a soundtrack album for the series.
Though the show was on for only a year and a half, "The Untouchables" was able to tell a complete story, fleshing out both the heroes and the villains into complex characters, and it wrapped up most of the plot lines by the final episode.
This series would make an ideal DVD box set. Are you paying attention, Paramount?