The Doctor (Doctor Who) credits Tennant as "Doctor Who". The credit reverted to "The Doctor" for 2005's Christmas special "The Christmas Invasion" and all subsequent stories at Tennant's request. Matt Smith, Peter Capaldi and Jodie Whittaker have continued to be credited as "The Doctor". John Hurt plays a mysterious past incarnation of the Doctor in the 50th anniversary special "The Day of the Doctor", with minor roles in "The Name of the Doctor" and mini-episode "The Night of the Doctor", created as a "mayfly Doctor" by Steven Moffat. In the television episodes, he is credited as "The Doctor", but he is introduced as "The
D. M. S. Watson Naval Volunteer Reserve. He was later transferred to the nascent Royal Air Force where he worked on balloon and airship fabric design. Watson was married in 1917 to Katharine Margarite Parker, and had two daughters, Katharine Mary and Janet Vida. After World War I, Watson returned to academic study and in 1921 he succeeded Hill as the Jodrell Professor of Zoology and Comparative Anatomy and the curator of what is now the Grant Museum of Zoology at UCL. He devoted his energy to the development of the Zoology department there and consolidated his position as a respected academician. In 1922