The Worlds of Doctor Who (audio anthology)

 was a full cast audio anthology released in 2014 by Big Finish Productions to celebrate the fifteenth anniversary of the release of The Sirens of Time, the company's first Doctor Who release. It featured the crossover of a number of their Doctor Who spin-off ranges, namely Jago & Litefoot, Counter-Measures, Gallifrey and UNIT (in the form of the Companion Chronicles team featured in Tales from the Vault and Mastermind).

Publisher's summary
An epic adventure uniting the Doctor's friends across time and space, featuring Jago & Litefoot, Counter-Measures, the Vault and Gallifrey!

Stories

 * Mind Games
 * The Reesinger Process
 * The Screaming Skull
 * Second Sight