"Doctor Who" is one of the most important franchises in the history of television. The beloved sci-fi series, which debuted in 1963, has been revamped and spun-off countless times over the course of it's more than 50 years on the air. In honor of "Class," the latest project to come out of the Who-niverse — which debuts on BBC America on April, 15, 2017, and focuses on the students and staff of the fictional Coal Hill Academy — Wonderwall.com is taking a look back at all 12 iterations of the Doctor and what the show's stars are up to now, starting with current Doctor Peter Capaldi, who took over the role in late 2013. He previously appeared in "Paddington," "The Fifth Estate," "World War Z" and "Dangerous Liaisons" and won an Oscar in 1995 for his work on "Franz Kafka's It's a Wonderful Life," which he wrote and directed. In 1991, Peter wed Elaine Collins, with whom he shares daughter Cecily. He announced in early 2017 that he plans to leave "Doctor Who" at the end of the year. Now keep reading for more!
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Doctor No. 11: Matt Smith, 2010 – 2013
Matt Smith was still relatively new to the acting game when he was chosen as the 11th incarnation of the Doctor in January 2009. Before "Doctor Who," the Northamptonshire native's most noteworthy role was a 2007 stint on U.K. series "Party Animals." In fact, the aspiring footballer never intended to pursue acting professionally. It wasn't until a back injury sidelined his athletic aspirations that a teacher convinced him to join the National Youth Theatre. Matt went on to study drama at the University of East Anglia. Small theater and television roles followed until — after three weeks of auditioning — Matt became the youngest actor ever to portray the Doctor.
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Portraying the Doctor certainly has its perks! In 2006, David Tennant's Time Lord carried the Olympic torch in a memorable episode of "Doctor Who." In real life, eleventh Doctor Matt Smith was granted the same honor, carrying the torch through Cardiff for the 2012 London games. But the responsibilities of portraying the role can be taxing as well: In November 2011, work commitments caused the collapse of Matt's 18-month relationship with model Daisy Lowe. He eventually moved on with "Cinderella" actress Lily James after they fell for each other on the 2014 set of "Pride and Prejudice and Zombies." Matt, who ended his run as the Doctor in December 2013, has also appeared in "Terminator Genisys" and in Ryan Gosling's directorial debut, "Lost River." He also portrays Prince Philip on the hit Netflix series "The Crown."
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Doctor No. 10: David Tennant, 2005 – 2010
David Tennant claims he was just 3 years old when he told his parents that he wanted to be an actor. Why? His passion for the "Doctor Who" franchise! As a child, the avid "Doctor Who" fan even met the fourth incarnation of the Doctor, Tom Baker, at a book signing. The Scottish star showed a talent for acting at an early age and auditioned into the Royal Scottish Academy of Music and Drama at age 16. There, he changed his name in honor of Pet Shop Boys frontman Neil Tennant (his real last name is McDonald). During the '90s, he performed frequently with the Royal Shakespeare Company while simultaneously winning roles on television and in film, including a part in "Harry Potter and the Goblet of Fire." In 2005, he was hired to replace Christopher Eccleston in the second season of the revamped "Doctor Who."
David Tennant resigned as the Doctor in 2009 after three seasons. He's since appeared in the 2011 "Fright Night" remake, voiced a character in "How to Train Your Dragon" and its TV offshoots and starred on "Jessica Jones" and "Broadchurch," plus its American remake, "Gracepoint." In a twist of fate that proves David may truly be the biggest "Doctor Who" fan in existence, he wed actress Georgia Moffett — the daughter of actor Peter Davison, who played the fifth incarnation of the Doctor — on Dec. 30, 2011. Earlier that year, they welcomed a baby girl, Olive. They added son Wilfred to their brood in 2013 and another daughter in 2015. David also adopted Georgia's son from a previous relationship, Ty.
Doctor No. 9: Christopher Eccleston, 2005
When the BBC revamped "Doctor Who" in 2005 after almost a decade off the air, Christopher Eccleston was already a household name in the U.K. thanks to his role on "Our Friends in the North." (Before that, he worked a series of odd jobs including posing nude as an art school model and working at a grocery store before his big break at age 27.) While he may not have been considered an A-list star stateside in 2005, the British actor had already appeared in various Hollywood fare, from "Elizabeth" and "eXistenZ" to "Gone in Sixty Seconds" and "28 Days Later."
Christopher Eccleston's time as the Doctor was to be short-lived. He bowed out of the series after just one season, calling the experience "mixed" during a BBC radio interview. He's since appeared in "G.I. Joe: The Rise of Cobra" and "Thor: The Dark World" and can currently be seen on HBO's "The Leftovers." In November 2011, he wed a copy writer named Mischka. They welcomed a son, Albert, in early 2012 and a daughter, Esme, in 2013 before parting ways in late 2015.
Doctor No. 8: Paul McGann, 1996
Paul McGann attended the Royal Academy of Dramatic Art before scoring his first big break in 1982 with "Give Us a Break." Roles in various British programs followed until the Liverpool native ventured into Hollywood fare with "Empire of the Sun" and "Alien 3." He was even considered a member of the "Brit Pack," a group of young rising British talent that also included Colin Firth, Gary Oldman and Tim Roth. The actor welcomed two sons, Joe and Jake, with stage manager Annie Milner, with whom he worked on a production of "Much Ado About Nothing." The couple made it official in 1992. But just a few years later, Paul got his first taste of scandal when he was snapped smooching his "Catherine the Great" co-star Catherine Zeta-Jones. In 1996, the actor made headlines once again when he was cast as the eighth incarnation of the Doctor.
Paul McGann starred as the Doctor on the 1996 "Doctor Who" made-for-TV movie, a joint venture between the BBC and Hollywood, alongside seventh Doctor Sylvester McCoy. The film was intended to serve as a backdoor pilot for a revamped series, but while it was successful in the U.K., it failed to attract an American audience. Paul only portrayed the Doctor on television one more time: on a 2013 episode of the show — though he has lent his voice to various "Doctor Who" audio plays over the years. He continues to appear on British television, and most notably, starred in the 2002 adaptation of Anne Rice's "Queen of the Damned" and on several episodes of "Luther" between 2010 and 2011. In late 2006, Paul and his wife divorced after 15 years of marriage. He rebounded with actress Susannah Harker, but they reportedly called it quits in 2008.
Doctor No. 7: Sylvester McCoy, 1987 – 1989 and again in 1996
Sylvester McCoy, who was born Percy James Patrick Kent-Smith, trained for the priesthood before launching a comedy act with The Ken Campbell Roadshow and adopting his stage name. He worked frequently throughout the '70s and '80s before taking over the role of the Doctor in 1987. The Scottish star reprised the part on the 1996 made-for-TV movie.
In 2012 — a decade after he auditioned for the role of Bilbo Baggins in "The Lord of the Rings" — Sylvester McCoy appeared in "The Hobbit: An Unexpected Journey" as wizard Radagast the Brown. He returned to the role in the next two installments of the trilogy: "The Desolation of Smaug" in 2013 and "The Battle of the Five Armies" in 2014. Sylvester and his wife reportedly have two sons together.
Doctor No. 6: Colin Baker, 1984 – 1986
Colin Baker studied at the London Academy of Music and Dramatic Art before launching his professional career on various British programs throughout the '70s. After they co-starred on "The Brothers" in the mid-'70s, Colin and actress Liza Goddard were briefly married. In 1984, the native Londoner was selected as the sixth incarnation of the Doctor after previously appearing on the show as another character. But the win was marred by tragedy: Shortly after he was offered the part, Colin's baby boy, Jack, died from Sudden Infant Death Syndrome. (His mother was actress Marion Wyatt, Colin's second wife.) Three years later, he was let go by the BBC as part of their efforts to refresh "Doctor Who." Rumors have long plagued his firing: Liza reportedly romanced Michael Grade, the man responsible for firing Colin from "Doctor Who," after she and the actor divorced.
Colin Baker and his second wife now have four daughters. The former Time Lord is still active in the "Doctor Who" community, lending his voice to audio plays. He even served as the president of the Doctor Who Appreciation Society. He continues to appear on stage and on television, though he's yet to replicate a "Doctor Who" level of success again in his career.
Doctor No. 5: Peter Davison, 1981 – 1984
Peter Davison, who was born Peter Moffett, started acting at an early age. In 1973 when he was just 21 years old, he married teacher Diane Russell, though their marriage was to be short-lived. He met his second wife, actress Sandra Dickinson, while they were working together on "The Tomorrow People." They tied the knot in December 1978 and worked together occasionally, though Peter struggled to find consistent work throughout the '70s. He was offered the role of the fifth Doctor when he was 29 in 1981.
In 1984, Peter Davison and his second wife welcomed a daughter, Georgia Moffett. (She married tenth Doctor David Tennant on Dec. 30, 2011.) But it wasn't meant to be: Their marriage ended contentiously in 1994. In 2003, he married writer Elizabeth Morton, with whom he now shares two sons, Louis and Joel. Peter continues to appear regularly on the stage and on the small screen, most notably on "Law & Order: U.K." from 2011 to 2014.
Doctor No. 4: Tom Baker, 1974 – 1981
Tom Baker spent six years preparing to become a Roman Catholic monk before losing his faith. The Liverpool native served in the Royal Army Medical Corps in the '50s and wed Anna Wheatcroft in 1961. They had two sons, Daniel and Piers, before they divorced in 1966. It wasn't until the late '60s that Tom started acting professionally. Eventually, he joined the National Theatre Company, where he befriended Sir Laurence Olivier, who recommended him for a role in the 1971 film "Nicholas and Alexandra." He earned two Golden Globe nominations for the performance. A few years later, while working on a construction site due to the scarcity of acting roles at the time, Tom was hired as the fourth incarnation of the Doctor.
Tom Baker fell in love with his "Doctor Who" companion Romana II — or, more specifically, her real-life alter ego, Lalla Ward. They wed in December 1980, but the marriage lasted just 16 months. In 1986, Tom married "Doctor Who" assistant editor Sue Jerrard. He still works regularly in the U.K., primarily as a voice actor.
Doctor No. 3: Jon Pertwee, 1970 – 1974
Jon Pertwee was a bit of a troublemaker as a boy: The London native was expelled from several schools, including the Royal Academy of Dramatic Art. During World War II, he served in the Royal Navy, where he reported directly to Winston Churchill as part of the secretive Naval Intelligence Division. After the war, Jon launched his career as a comedic actor. He wed his first wife, Jean Marsh, in 1955, though they divorced in 1960. That same year, he married Ingeborg Rhoesa, with whom he had a daughter, Dariel, and a son, Sean. In 1970, he assumed the role of the Doctor from Patrick Troughton.
After four years as the Doctor, Jon Pertwee resigned to resume his career as a stage actor. He continued to work in the U.K. until he died from a heart attack in Connecticut on May 20, 1996. He also wrote two autobiographies before his death.
Doctor No. 2: Patrick Troughton, 1966 – 1969
Patrick Troughton started acting as a teenager and studied at the Embassy School of Acting at Swiss Cottage before relocating to Long Island, New York. The Middlesex native returned home — after escaping via lifeboat when his Belgian vessel struck a sea mine — during World War II and joined the Royal Navy. He even saw some action. Patrick returned to the theater in 1945. He appeared in Laurence Olivier's "Hamlet," won a small role in 1950's "Treasure Island" and in 1953, became the first actor to portray Robin Hood on television. Around this time, he divorced his first wife, Margaret. Patrick was already an established actor when he won the part of the Doctor in 1966.
Patrick Troughton left "Doctor Who" in 1969 due to the series' grueling schedule. He wed Shelagh Dunlop, with whom he had six children: daughters Joanna and Jane and sons David, Michael, Peter and Mark. But he developed a heart condition and as a result, suffered heart attacks in 1979 and 1984. He died from a third heart attack on March 29, 1987, two days after his 67th birthday. Patrick was in Columbus, Georgia, where he was participating in the Magnum Opus Con II science fiction convention, when he passed away. Two months earlier, he'd appeared on the very first episode of "Inspector Morse" (pictured).
Doctor No. 1: William Hartnell, 1963 – 1966
William Hartnell, who never knew his father, was a troubled child who often committed petty crimes and struggled with school throughout his youth. He discovered the theater in 1925 and appeared in several Shakespeare plays before World War II, during which he served in the Tank Corps before suffering a nervous breakdown. William returned to acting and was doing quite well for himself when he originated the role of the Doctor in 1963. He was married to Heather McIntyre from 1929 until his death. They had one child, daughter Heather Anne.
William Hartnell suffered from arteriosclerosis, which eventually led to his resignation from "Doctor Who" in 1966. He reprised his role as the first Doctor on the 1973 special "The Three Doctors," but it was to be his last performance. The British actor spent the last year of his life living permanently in a hospital, where he suffered a series of strokes brought on by cerebrovascular disease, before dying as a result of heart failure on April 23, 1975.