In the 2017 Christmas special "Twice Upon a Time", the First and Twelfth Doctors unwittingly intervene when Testimony, an organization in the far future that collect memories from those about to die, retrieve a captain in the First World War from the moment before his death, the temporal anomaly of the two Doctors resisting their imminent regenerations disrupting Testimony's efforts to return the captain to his scheduled death. The Doctors are able to bend the rules and return the captain to a point a couple of hours after he was taken out of time, in time for his life to be saved by the Christmas truce. Before he returns to time, the captain reveals that his name is Archibald Hamish Lethbridge-Stewart, suggesting that he is a relative of the Brigadier. (It is confirmed that the character is one of the Brigadier's grandfathers.)