The television series employed a set of characters completely different from the original book series (the film and radio series used the characters from the books). The major
protagonists were: • Michael Upton (
Barry Evans), an easy-going, serious and somewhat anxious son of a doctor who is essentially following in his father's footsteps. Upton was the central character of the first two series, but Barry Evans left the show following
Doctor at Large. • Duncan Waring (
Robin Nedwell), Michael's best friend and roommate. He is just as bright as Upton, but far less serious in his studies, although he generally does well. After Barry Evans left the show, Nedwell returned as Waring to become the focus of the show. Duncan Waring appears in all of the series except
Doctor at Large, and is the main protagonist of the last five. • Dick Stuart-Clark (
Geoffrey Davies), a thirtyish student who deliberately fails his courses in order to take advantage of his late grandmother's will, which bequeathed him a large sum of money for each year he is in medical school. He later becomes an anesthetist who prefers partying and chasing women to his medical duties. Dick Stuart-Clark is the only character present throughout all seven series. Davies and Nedwell essentially became a
double act in many of the later episodes of the franchise. • Paul Collier (
George Layton), a less competent student and friend of Upton and Waring. His character left the series after
Doctor in Charge, but Layton continued to write scripts for the subsequent series, and reprised the Collier character for the later BBC series
Doctor at the Top. • Lawrence Bingham (
Richard O'Sullivan), a brilliant, but arrogant and irritating doctor who believes he is the best of all possible doctors. He marries the equally obnoxious Dr. Mary Parsons (
Helen Fraser) in the series
Doctor in Charge. His need to continually impress her is the source of much comedy. O'Sullivan departed after
Doctor in Charge to star in
Man About the House The main antagonist is the well-respected and ill-tempered surgeon Professor (later Sir) Geoffrey Loftus (
Ernest Clark). Many of the plot lines revolve around the students' attempts to meet his demanding expectations. Another hospital official with whom the students have contact is the Dean (
Ralph Michael), who is more interested in the hospital's
Rugby union team than he is in medicine. Other characters in the early episodes, some of whom later reappeared for single episodes in subsequent series, include: • Danny Hooley (
Jonathan Lynn), an Irish medical student who is a friend of Waring, Collier, Upton and Stuart-Clark. He later returns as an 'out-of-work doctor' in the
Doctor in Charge episode "Should Auld Acquaintance be Forgot?" • Huw Evans (
Martin Shaw), a Welsh medical student, another friend of the four students. He reappears as a very nervous expectant father in the episode "Mother and Father Doing Well". • Dave Briddock (Simon Cuff), another friend of the students. He spends part of the series living with Helga, his Swedish girlfriend. ==Guest stars==