Ian Bancroft was a veteran Watcher who always stayed within the rules. He tried never to let his subjects involve his emotions. He was the long time Watcher of the immortal Darius and was reassigned to May-Ling Shen after Darius' death.
In 1968, as a soldier, he introduced a badly wounded soldier, Joe Dawson, to the Watchers when they were both in Vietnam, after Joe's life was saved by an Immortal. He explained the Immortals and the role of their Watchers, giving Joe an option to the suicide he was considering, and a new purpose in his life.
After the death of May-Ling Shen, he took a trip to Seacouver to call on his protege, Joe Dawson, and take a few days to indulge in Joe's notorious all Watcher poker game. Also there was Rita Luce with whom he had words, she was appalled at his apparent lack of emotion regarding the deaths of his assigned Immortals, while he was appalled at her over-emotionalism.
He later realized Rita was more than just emotional, but had deliberately made a catastrophic breach of her oath; and was feeding information to her assignment, giving him intelligence on other Immortals garnered from Watcher gossip. Her interference allowed her Immortal, Michael Christian, to murder older and more experienced Immortals with little threat to himself.
Ian promised to make sure she was expelled from the Watchers. Her obsession with Christian drove her to kill the threat to them: Bancroft. She ran him down in the street, and left him for dead.