"Detective Opera Milky Holmes") is a media franchise owned by the Japanese entertainment company Bushiroad.

Other media includes a manga adaptation serialized in Comp Ace between May 2010 and January 2011; two visual novels, released for the PlayStation Portable in December 2010 and August 2012 respectively; a trading card game tie-in with Bushiroad's Weiß Schwarz; and a light novel series published by ASCII Media Works under their Dengeki Bunko label.

Set in the near future in the Great Era of Detectives, chosen people are born with supernatural abilities known as Toys (トイズ, Toizu).

The Alternative TV specials also take place in this universe, in which Kobayashi and Milky Holmes are assisted by another Toy user, Lily Adler, in fighting against the Thieves' Empire whilst visiting London.

In the first two anime television series, the four girls of Milky Holmes, Sherlock, Nero, Hercule and Cordelia, end up losing their Toys during an encounter with the Thieves' Empire.

Taken away from their rich lifestyle and thrown into an attic, the girls must try to regain use of their Toys or else face expulsion from Holmes Detective Academy.

A manga adaptation illustrated by Sorahiro Mizushima was serialized in Kadokawa Shoten's Comp Ace magazine between May 2010 and January 2011 and was published into two tankōbon volumes.

An anime adaptation of Tantei Opera Milky Holmes by J.C. Staff aired between October 7, 2010 and December 23, 2010 and was also streamed by Crunchyroll.

The Two of Us are Milky Holmes), co-produced with Nomad, aired between July 13, 2013 and September 28, 2013, alongside live action segments featuring the cast.

[16] Players play the role of Opera Kobayashi, who must train Milky Holmes to be great detectives and use their abilities to stop thieves.

[17] A sequel, Tantei Opera Milky Holmes 2, was released on August 23, 2012, casting players in the role of a new protagonist named Ellery Himeyuri.

The voice actresses also make a cameo as the Milky Holmes in episode 23 of Fire Leon, a live action series also produced by Bushiroad.

Additionally, the character "Sherlock "Sheryl" Shellingford" appears as a "guest" partner in the Japanese MMORPG Onigiri Online.

An idea of a movie adaptation was first teased in the form of clues hidden within the end cards of the delayed fifth episode of Tantei Kageki Milky Holmes TD for fans to solve.