|First Appearance:||An Unearthly Child|
|Portrayed by:||William Russell|
Ian Chesterton was a science teacher in Coal Hill School when he first met Susan Foreman and Barbara Wright. He then met the First Doctor inside a junkyard, 76 Totter's Lane. He then travelled with the Doctor and Susan and Barbara to different planets and Earth in the past and future. He and Barbara left the TARDIS crew after meeting the Daleks for the third time, deciding they had had enough.
When he and Barbara became suspicious of the 15-year-old girl, Susan, they went to investigate 76 Totter's Lane and discovered the First Doctor and his TARDIS inside a junkyard. He and Barbara were kidnapped by the Doctor inside his time and space ship and taken back to 100,000BC. Ian didn't believe that they had travelled in time at first, but soon came to believe when he and the other were chased by the Tribe of Gum and captured. However, he helped the others to escape and return to the TARDIS before the cavemen realised. (An Unearthly Child)
While trapped on Avalon, Ian helped the Doctor and band of Seven Companions including, Kilvenny Odoyle, Sir Bron of Westhold and Alammar of Silverwood in order to capture Merlin's Helm. After succeeding, Ian helped fight Gramling and Marton Dhal in the Siege of Fluxford. (The Sorcerer's Apprentice)
Ian and Barbara visited Baltimore with the Doctor where they met Edgar Allan Poe and fought a demonic ram. (The True and Indisputable Facts in the Matter of the Ram's Skull)