Actor: William Hartnell
Companions: Susan (Grand-daughter), Ian, Barbara, Vicki, Steven, Katarina, Sara, Dodo, Polly, Ben
Enemies: Daleks, Meddling Monk, Cybermen
Last Adventure: Worn out from battling the Cybermen, the Doctor regenerates in front of Ben and Polly
Actor: Patrick Troughton
Companions: Ben, Polly, Jamie, Victoria, Zoe
Enemies: Cybermen, The Great Intelligence, Ice Warriors, Time Lords
Last Adventure: After calling the Time Lords for help, the Time Lords capture the Doctor and put him on trial for interfering in the universe (a Time Lord no-n0). They maroon him on Earth and force a regeneration.
Actor: Jon Pertwee
Companions / Assistants: Liz, Jo, Brigadier, Sarah Jane
Enemies: Autons, the Master, Sontarans
Last Adventure: Battling sentient spiders, he regenerated after radiation poisoning on Metebelis III in front of the Brigadier and Sara Jane
Actor: Tom Baker
Companions: Sarah Jane, Harry, Brigadier, Leela, K-9, Romana I & II, Kamelion, Adric, Nyssa, Tegan
Enemies: the Master, Daleks, Cybermen
Last Adventure: Battling the Master, the Doctor falls from a satellite dish, forcing a regeneration in front of Adric, Nyssa and Tegan.
Companions: Sarah Jane, Harry, Brigadier, Leela, K-9, Romana I & II, Kamelion, Adric, Nyssa, Tegan
Enemies: the Master, Daleks, Cybermen
Last Adventure: Battling the Master, the Doctor falls from a satellite dish, forcing a regeneration in front of Adric, Nyssa and Tegan.
Actor: Peter Davison
Companions: Tegan, Nyssa, Adric, Turlough, Kameleon, Peri
Enemies: the Master,Cybermen, the Black Guardian,
Last Adventure: After being poisoned along with Peri, the Doctor receives enough antidote for one person, he gives the dose to Peri and the poison forces his regeneration.
Actor: Coling Baker
Companions: Peri, Melanie
Enemies: Cybermen, Daleks, Time Lords, the Rani
Last Adventure: Having defeated the Valeyard, (an evil future incarnation of the Doctor), the Doctor continues to travel with Melanie. When he ultimately regenerates, Melanie is unconscious and unaware of his regeneration.
Actor: Sylvester McCoy
Companions: Melanie, Ace
Enemies: the Rani, Cybermen, Daleks, the Master
Last Adventure: The Doctor was called upon to transport to transport the remains of the Master from Skaro (where he was executed) to Gallifrey. After the Master escaped, the Doctor landed on Earth where he was he shot multiple times. Anaesthetics given him by an Earth hospital hindered his regeneration cycle.
Actor: Paul McGann
Companions: Grace, Charlie, Lucie
Enemies: the Master, Cybermen,
Last Adventure: Trying to save a woman from a crashing ship, the Doctor fails to make it back to the Tardis in time. Crash landing on the planet Skarn, the Sisters of the Flame help him force a new regeneration to help fight in the Time Wars.
Actor: Christopher Eccleston
Companions: Rose, Captain Jack
Enemies: Autons, Daleks
Last Adventure: After Rose Tyler inhaled the heart of the Tardis, the Doctor sacrificed himself to draw the energies which were fatal to Rose, out of her. No one is meant to do that, not even a Time Lord. Though channelling the energies back into the Tardis, he was forced to regenerate.
Actor: David Tennant
Companions: Rose, Mickey, Martha, Donna, Captain Jack
Enemies: Cybermen, Daleks, Cassandra, Weeping Angels, Sontarans, The Master
Last Adventure: The Doctor absorbs a dangerous amount of radiation after Donna's father accidentally triggers the dose. The Doctor doesn't regenerate immediately and has time to say good-bye to all his former companions before he does so.
Actor: Matt Smith
Companions: Amy, Rory, River Song, Clara
Enemies: Daleks, Cybermen, Sontarans, Weeping Angels, Silurians, the Silence, the Great Intelligence
Last Adventure: Yet To Be Seen
Other Actors Who Have Played the Doctor
Actor: Peter Cushing (Grand Moff Tarkin)
Story: Doctor Who and the Daleks / Daleks Invasion of Earth: 2150 A.D.
Notes: Peter Cushing played Dr. Who in two films which were are not considered canon. Dr.Who creates a time machine and takes his family on a trip through time.
Actor: Richard Hurndall
Story: the Five Doctors
Notes: Richard Hurndall portrays the first Doctor in the Five Doctors episode. Though not the same actor, he is considered canon.
Actor: Rowan Atkinson (Mr. Bean)
Story: Curse of the Fatal Death
Notes: In a spoof of Doctor Who, Rowan plays an alternate ninth Doctor briefly before he is forced to regenerate while battling the Master and the Daleks. The Doctor regenerates several times in the same episode and other actors who have played the Doctor include, Richard E. Grant, Jim Broadbend, Hugh Grant and Joanna Lumly