Andrea makes her mark

New army consultant LT Col Andrea Petersen (played by Luanne Gordon) arrives and immediately riles Selena by being mean to an overweight patient suffering a heart attack. Andrea gets angry when she finds Guppy treating a patient for Nadia and makes Kelsey do it instead. Greg admits to Cyd that Andrea is the reason why he found it difficult to commit to her. In resuscitation, Selena and Andrea argue over a patient's treatment. Andrea leaves resus to find Greg and is stopped by Kelsey asking her to help treat another patient. When Andrea finally catches up with Greg in the staffroom, she reminds him that he promised to wait a year for her and forces him to choose between her and Cyd. Later, Cyd is left devastated when she spots Greg and Andrea kissing in an ambulance. Also, Jeff and Dixie pick up an elderly patient who hyperventilated when her son took her up in his plane to fulfil a promise to her dead pilot husband. VIDEO: Watch preview of Casualty