10 Longest Gaps Between Doctor Who Character Appearances
3. Alpha Centauri (15,751 Days)
In another cheeky Hail Mary by Mark Gatiss and Steven Moffat (and once again in their final Doctor Who series), the duo brought back Alpha Centauri, a niche Doctor Who character who hadn't been seen or heard from in decades.
The memorably-designed character was once described by director Lennie Mayne as "a giant green dick." Alpha Centauri appeared as such in the closing moments of Empress of Mars, and was again voiced by Ysanne Churchman, reprising the role after 43 years.
Alpha Centauri wasn't a cheap bit of fan service either - it actually made sense to the context and themes of Gatiss' story. Airing as Britain made plans to leave the European Union, it portrays the great Martian Empire's decision to join the wider Galactic community. The first representative they meet is Alpha Centauri, last seen in 1974's The Monster of Peladon.
Aside from the political parallels, getting a giant green dick back on primetime BBC1 was exactly the sort of mischievous move you'd expect from Moffat and Gatiss.