Million Dollar Haul is the second of three films made by Poverty Row producer Bert Sternbach starring Tarzan the Police Dog. (The other two were Inside Information, 1934, and Captured in Chinatown, 1935.) For a brief period in the 1930s, Tarzan's popularity rivaled that of his chief competitor, Rin-Tin-Tin. A series of mysterious robberies have struck a Los Angeles import company. The board of directors enlists federal agent Dan Kennedy and his police dog, Tarzan, to pursue the thieves. It isn't all work for the G-Man, however, as he begins a romance with the company's pretty blonde secretary, Sheila. Dan believes that his girlfriend's father may be behind the robberies. But when Sheila is kidnapped, Dan realizes that the true culprit is still on the loose.
Leading man Reed Howes had been a matinee idol during the silent era, usually cast in Westerns and serials. Shortly after completing this film, he would play John Wayne's rival in The Dawn Rider (1935). William Farnum's career also dated back to the silent years. Considered Fox's biggest male box-office draw in the 1910s, he starred in the original Hollywood versions of The Sign of the Cross (1914), A Tale of Two Cities, and Les Miserables (both 1917). Margaret McConnell, a relative of Woodrow Wilson's, landed a part in Million Dollar Haul after being named College Humor and Sense magazine's "All-American College Girl of 1933". Unfortunately, this did not lead to any further roles for the aspiring actress.