While not as highly regarded in some circles as its premium cable rival HBO, Showtime has produced a number of great original shows; the 5 best Showtime series ever contain content that could not be shown on network TV or basic cable, allowing them to push the envelope of visual storytelling on television. The best Showtime series ever build on the groundbreaking premium cable series of HBO, taking turns into darker, often more explicit territory.
- "Dexter" – The best Showtime series ever, without a doubt, is "Dexter." It's a cop show with a unique twist: the protagonist, Dexter Morgan, a blood-spatter expert for the Miami Metro Police Department, moonlights as a serial killer of serial killers. An adopted boy with a tragic past, his guardian, Miami cop Harry Morgan, noticed patterns of behavior consistent with a budding serial killer, channeling his instincts and giving him a code to work with, one of the major rules being that he could not kill an innocent man. "Dexter" unfolds with complicated plotting, bloody action, and dark humor, all on the back of the stellar lead performance by Michael C. Hall as the serial killer everyone has come to love.
- "Penn & Teller: B.S.!" – The renowned comic magicians take their show on the road to find the B.S. behind many of today's trends, issues, and causes, from PETA (finding out that the animal rights organization kills animals at their no-kill shelters) to the link between video games and violence. Natural skeptics, their methods are insightful, sometimes crude, and often hilarious, making it one of the best Showtime series ever.
- "Brotherhood" – Showtime's attempt at gangster drama following HBO's success with "The Sopranos" may not reach that classic show's lofty heights, but its depiction of corruption in the city of Providence, Rhode Island is an interesting, slowly-unfolding drama with many vivid characters, not least of which are the show's two leads, Jason Clarke and Jason Isaacs, as brothers on either side of the law.
- "The Tudors" – The story of Henry VIII and his six wives told in steamy—and explicit—soap opera fashion may not be historically accurate, but it makes for compelling viewing and one of the best Showtime series ever.
- "Weeds" – Like the best premium cable programming, "Weeds" takes something familiar—in this case, the family comedy—and twists it into darker places, with a suburban mom becoming a drug dealer to make ends meet. The result is comedy and drama in their most bizarre forms.