Mai Kuraki x Meitantei Conan Collaboration Best 21: Shinjitsu wa Itsumo Uta ni Aru!

Mai Kuraki x Meitantei Conan Collaboration Best 21: Shinjitsu wa Itsumo Uta ni Aru! (倉木麻衣×名探偵コナン COLLABORATION BEST 21 -真実はいつも歌にある！-) is the fourth greatest hits album by Japanese singer-songwriter Mai Kuraki. It was released on 25 October 2017 by Northern Music, in celebration of Kuraki's long-time collaboration with the Japanese animation Case Closed. The album features all the songs Kuraki had written for the animation.

Chart performance
In Japan, the album debuted at number four on the Oricon Weekly Albums Chart, selling 25,819 copies in its first week. The album also debuted at number four on the Billboard Japan Hot Albums Chart. The album was announced as Japan's 86th biggest selling album of the year.

The first single from Mai Kuraki x Meitantei Conan Collaboration Best 21: Shinjitsu wa Itsumo Uta ni Aru!, "Togetsukyo (Kimi Omou)" was released in April 2017 and peaked at number two on the Billboard Japan Hot 100 chart. The song has sold over 250,000 download copies and 76,146 physical copies, making it her best-selling CD single in decade and the most downloaded song in her career.

Detective Conan theme songs in media

 * "Secret of my heart" was used as the 9th ending theme
 * "Start in my life" was used as the 11th ending theme
 * "Always" was used as the 12th ending theme and as the theme song for its 5th movie Countdown to Heaven
 * "Winter Bells" was used as the 10th opening theme
 * "Time After Time" was used as the theme song for its 7th movie Crossroad in the Ancient Capital
 * "Kaze no La La La" was used as the 12th opening theme
 * "Growing of my heart" was used as the 16th opening theme
 * "Shiroi Yuki" was used as the 26th ending theme
 * "Ichibyou Goto ni Love for you" was used as the 23rd opening theme
 * "Revive" was used as the 25th opening theme
 * "Puzzle" was used as the theme song for its 13th movie The Raven Chaser
 * "Summer Time Gone" was used as the 29th opening theme
 * "Tomorrow is the last time" was used as the 36th ending theme
 * "Your Best Friend" was used as the 40th ending theme
 * "Koi ni Koishite" was used as the 43rd ending theme
 * "Try Again" was used as the 35th opening theme
 * "Muteki na Heart" was used as the 48th ending theme
 * "Dynamite" was used as the 39th opening theme and being one of the theme songs in TV special The Disappearance of Conan Edogawa: The Worst Two Days in History
 * "Sawage Life" was used as the 52nd ending theme
 * "Yesterday Love" was used as the 53rd ending theme
 * "Togetsukyo -Kimi Omou-" was used as the 55th ending theme and the theme song for its 21st movie The Crimson Love Letter