Plot synopsis: Mercy is a medical drama which aired on NBC from September 23, 2009 to May 12, 2010. The series initially aired on Wednesday nights at 8/7c, as part of the 2009 fall season, but was pushed back to 9/8c in April. On October 23, 2009, Mercy was picked up for a full twenty-two-episode first season. On May 14, 2010, NBC announced that Mercy had been cancelled and would not return for a second season due to low ratings.