Bill Filer

Bill Filer was an American agent sent to discuss the threat of the Master with UNIT.

Being shut out of the rest of the proceedings by Chinn, he left intending to return to his base of operations. On his way back he passed by Axos. Intending to investigate, he was captured by the ship, scanned, duplicated and held prisoner with the Master.

His shouts for help were heard by Jo when she and the Doctor visited the ship and got lost inside it. With the Master's help, he escaped and arrived at the complex just in time to help destroy the duplicate of him.

For the remainder of the crisis, he helped the Doctor and UNIT defeat the Axons and the Master. (DW: The Claws of Axos)