Unriddle is a highly gripping Singaporean television drama series broadcast on MediaCorp Channel 8 from 2010 to 2012. Created by Screenplay Productions and famously known as 'Wu Xie' in Mandarin, the series successfully carved a niche for itself through its amalgam of mystery, action, and drama that kept the audience on the edge of their seat, right from the commencement to culminating episodes.

At the heart of the series is the protagonist Ruo Yun, brilliantly played by popular actress Rui En. Ruo Yun is a high-ranking CID officer, known for her sharp mind, courage, and relentless perseverance. The character is charmingly complex; she has an indomitable spirit and a sense of justice that observers might find bracing in its intensity but is undeniably appealing. On the other hand, her unconventional methods and the darkness and anguish she harbors within herself provide a fascinating contrast and balance to her character.

Ruo Yun's journey through the series is accentuated by her close colleague and friend, Hu Xiao Man, who is portrayed by the talented actress Chen Liping. Hu Xiao Man is the yin to Ruo Yun's yang. While Ruo Yun shells out justice with uncompromising intensity, Hu Xiao Man playfully brings a sense of humor, warmth, and light-heartedness to the plot.

The series takes the viewers through their day-to-day lives, the crimes they solve, the numerous puzzles they unravel, and the personal and professional struggles they undergo. What sets Unriddle apart is the way it integrates the crime-solving sequences leanly into the narrative. Each faced with a unique combination of criminals and heinous crimes that unfold in an unpredictable, gut-twisting manner. The show does an impeccable job of building tension and suspense, through clever plot construction and stunning visual storytelling.

The cast is further complemented by a repertoire of remarkable performances from the supporting actors, including Tay Ping Hui, Andie Chen, and Zhou Ying. They play significant roles in sprucing up the narrative and lending additional depth and variety to the series. Relationships, love, loyalty, and betrayal form an integral part of the narrative, weaving a compelling portrait of humanity's varied hues under the overarching theme of crime-solving mystery and suspense.

Visually, the series is captivatively gritty, with the conspiracy, morbid crimes, and darker aspect of the city's undertones. Unriddle's technical aspects are sharp, be it the cinematography, editing, or the art design – each frame is crafted to enhance the atmosphere of suspense. Moreover, the series is skillfully paced, with the progression of storylines, development of characters and rendering of suspense, engaging the viewers consistently throughout.

Throughout the series' run, Unriddle cleverly shifts the narrative gears. Each gear shift is marked by a significant plot twist or character development that tests the audiences' understanding and anticipation, only to leave them astounded and intrigued for more. Although the series commonly uses the by-episode case procedures, overarching storylines and mysteries bind the fabric of the series, set to be uncovered as the series progresses.

Towards the end of 2010, Unriddle achieved significant public and critical acclaim leading to its sequel, Unriddle 2 which aired in 2012. The sequel promised to raise stakes higher than before, plunges deeper into the intertwined lives of Ruo Yun and Hu Xiao Man amid the steadily churning wheel of justice.

Unriddle is more than a crime-solving drama; it's a riveting exploration of human nature, relationships, and the countless shades of good and evil that exist within society. It never hesitates to question the principles of right and wrong, justice, and truth. The series has a depth that transcends beyond its characteristically dark tone, pulling the viewers into a vortex of emotion, intrigue, and thought-provoking debates, making it a must-watch for those seeking an intense, gripping TV viewing experience.