В ролях:
Song Joong-ki ... Captain Yoo Si Jin (aka Big Boss)
Song Hye-kyo ... Doctor Kang Mo Yeon (aka Beauty)
Jin Goo ... Sergeant Major Seo Dae Young (aka Wolf)
Kim Ji-won ... First Lieutenant Yoon Myung Ju
Kang Shin-il ... Lieutenant General Yoon (aka Yellow Tiger) (Myung Joo's father)
Kim Byeong-cheol ... Lieutenant Colonel Park Byeong-su
Park Hoon ... Sergeant Choi Woo Geun (aka Snoopy)
Choi Woong ... as Staff Sergeant Gong Cheol Ho (aka Harry Potter)
Ahn Bo-hyun ... Sergeant Im Gwang Nam (aka Piccolo)
Kim Min Seok ... Lance Corporal Kim Gi Beom
Onew ... Lee Chi Hoon (1st year resident of Thoracic Surgery)
Lee Seung-joon ... Song Sang Hyun (General Surgeon)
Seo Jeong-yeon ... Ha Ja Ae (ER Nursing Team)
Park Hwan-hee ... Choi Min Ji (ER Nurse)
Hyun Jyu-ni ... Pyo Ji Soo (Pathology Specialist)
Tae In Ho ... Han Suk Won (Chairman of Haesung Hospital)
Park Ah In ... Kim Eun Ji (Thoracic Surgery Specialist)
Jo Woo Ri ... Jang Hee Eun (1st Year Resident of Anesthesiology)
Jasper Cho ... Daniel Spencer (Peacemaker Emergency Doctor Team)
Jeon Soo-jin ... Ri Ye Hwa (Peacemaker Emergency Nurse Team)
David Lee McInnis ... David Agus (Gang Boss, former Delta Force Captain)
Dean Dawson ... the Chief of Police (Tae Baek Police Chie
Jo Jae-yoon ... Jin Young Soo
Lee Yi-kyung ... Kang Min Jae
Zyon Barreto ... Fatima
David Pipes ... Martin (World Times reporter, episode 7)
Камео:
Lee Kwang-soo ... shooting arcade operator (episode 1)
Lee Jong-hyuk ... Captain Kim Jin Seok (episode 2, 5, 10, 15)
Matthew Douma ... US Army Delta Force Captain (episode 2, 10, 12)
Jung Ji Won ... TV announcer (episode 2)
Park Tae Won ... TV announcer (episode 2)
Ryu Hwa-young ... Seo Dae Young's ex-girlfriend (episode 4)
Jun In Taek ... Yoo Young Geun (Yoo Shi Jin's father) (episode 6, 7, 15)
Park Joon Geum ... Lee Chi Hoon's mother (episode 7, 11)
Yoo Ah-in ... bank reception (episode 13)
Nam Ki Ae ... Kang Mo Yeon's mother (episode 13)
Red Velvet ... themselves (episode 16)