The Hat Box Mystery (1947)

"Like-a-Jack-in-the-Box----Murder jumped out and claimed its Victim!"

Susan Hart, assistant to private detective Russ Ashton, is given a camera concealed in a hat box and assigned to take a picture of a woman. A gun is accidentally hidden in the box and the woman is killed. Susan is charged with murder, but Russ and his less-than-useful associate, Harvard, get on the case.