<Tr> <Td_colspan="2"> Next → Season 2 </Td> </Tr> <Tr> <Td_colspan="2"> List of Grey's Anatomy episodes </Td> </Tr> <P> The first season of the American television medical drama Grey's Anatomy, began airing in the United States on the American Broadcasting Company (ABC) on March 27, 2005, and concluded on May 22, 2005 . The first season introduces the main character, Meredith Grey, as she enrolls in Seattle Grace Hospital's internship program and faces unexpected challenges and surprises . Season one had nine series regulars, four of whom have been part of the main cast ever since . The season initially served as a mid-season replacement for the legal drama Boston Legal, airing in the Sunday night time slot at 10: 00, after Desperate Housewives . Although no clip shows have been produced for this season, the events that occur are recapped in "Straight to Heart", a clip - show which aired one week before the winter holiday hiatus of the second season ended . The season was officially released on DVD as two - disc Region 1 box set under the title of Grey's Anatomy: Season One on February 14, 2006, by Buena Vista Home Entertainment . </P> <P> The series' protagonist and title character is Dr. Meredith Grey (Ellen Pompeo), who is accepted into the residency program at the fictional Seattle Grace Hospital . She joins the program as an intern and is assigned to work under their resident Dr. Miranda Bailey (Chandra Wilson), along with fellow interns an extremely competitive Dr. Cristina Yang (Sandra Oh), an insecure Dr. George O'Malley (T.R. Knight), ex model Dr. Izzie Stevens (Katherine Heigl), and an arrogant Dr. Alex Karev (Justin Chambers). The surgical wing is primarily supervised by the Chief of Surgery Dr. Richard Webber (James Pickens, Jr .). Dr. Preston Burke (Isaiah Washington) is the head of Cardio surgery . Meredith is in a romantic relationship with her attending Derek Shepherd (Patrick Dempsey) a stranger she had a one - night stand with, and is the daughter of the renowned surgeon Ellis Grey (Kate Burton), who now suffers from Alzheimer's . </P>

When did the first grey's anatomy episode air