In the very first episode, _______ addresses X as "X Foreman", as this is the surname X's granddaughter Susan goes by, and the junkyard in which they find him bears the sign "I.M. Foreman". When addressed by Ian with this name in the next episode, X responds, "Eh? Y ? What's he talking about?" Later, when he realises that "Foreman" is not X's name, Ian asks Barbara, "Who is he? Y?" (In an ultimately-unused idea from documents written at the series' inception, Barbara and Ian would have subsequently referred to X as 'Y', given their not knowing his name.)
ID Y, the blanked out face. Right Click -->Open Link in new tab to expand the picture.
