Thunderbirds

Osgood told the Twelfth Doctor that Cloudbase was Thunderbirds, before Colonel Ahmed corrected Osgood and reminded her that Cloudbase was from Captain Scarlet. (TV: Death in Heaven)

Behind the scenes

 * Though the link isn't directly made in Death in Heaven, in the real world, Sylvia Anderson co-created both Thunderbirds and Captain Scarlet.
 * The original Thunderbirds TV series from 1965-1966 features the voices of a number of actors who also played roles on Doctor Who, such as Shane Rimmer, Jeremy Wilkin, David Graham and Ray Barrett. Cliff Richard and John Carson were involved in the feature-lengths films Thunderbirds Are Go (1966) and Thunderbird 6 (1968) respectively.
 * The 2015 reboot, Thunderbirds Are Go, also includes several actors involved in Doctor Who and its spin-off materials, such as David Menkin, Thomas Brodie-Sangster, Angel Coulby, Kayvan Novak, David Graham, Reggie Yates, Sandra Dickinson, Adjoa Andoh and Teresa Gallagher.
 * Sophia Myles, Ron Cook, Lex Shrapnel and Bhasker Patel all had roles in the 2004 live-action Thunderbirds film.