Luke Ward
From Tardis Wiki, the free Doctor Who reference
Luke Ward was the assistant of Sir George Stephenson and the son of Jack Ward.
Biography
Luke was hypnotised by the Master to lead Peri into the forest to pick herbs, but was actually leading her to mines which would turn people into trees. Unfortunately, he himself stepped on one and turned into a tree. His branches later saved Peri from stepping on one. (DW: The Mark of the Rani)
