Maureen "Mo" Effanga is a fictional character from the BBC medical drama Holby City, played by actress Chizzy Akudolu. She first appeared in the fourteenth series episode "Double Bubble", broadcast on 22 May 2012. Mo is a consultant cardiothoracic surgeon and a member of Holby's transplant team. She was introduced along with two other regular characters by the show's then executive producer Johnathan Young, who wanted more "truthful and complicated" characters in the series. When Akudolu read the character breakdown for Mo and learned that she was on the transplant team, she knew she wanted the part because she was passionate about organ donation as her brother has had a kidney transplant. The actress met with a heart consultant to help her prepare for the role.