After virtually all the Timely staff was let go in 1948 during an industry downturn, Colan began freelancing for National Comics, the future DC Comics. A stickler for accuracy, he meticulously researched his countless war stories for DC's "All-American Men at War", "Captain Storm", and "Our Army at War", as well as for Marvel's 1950s forerunner Atlas Comics, on the series "Battle", "Battle Action", "Battle Ground", "Battlefront", "G.I. Tales", "Marines in Battle", "Navy Combat" and "Navy Tales". Colan's earliest confirmed credit during this time is penciling and inking the six-page crime fiction story "Dream Of Doom", by an uncredited writer, in Atlas' "Lawbreakers Always Lose" #6 (Feb. 1949).