LOS ANGELES — About 45 minutes into “The Big Short,” Adam McKay’s “true story” — or so it says on the billboards — of Wall Street greed, the actor Finn Wittrock turns to the camera and confesses, “O.K., so this part isn’t totally accurate.”

No, he admits, the real-life counterpart to his character didn’t find a road map to the housing crisis of the mid-2000s lying around the marbled lobby of a JPMorgan Chase tower. Actually, he and his investing partner had heard and read about it elsewhere. But, hey, lighten up. It’s just a movie.

Mr. McKay and his team were trying to pre-empt the dreaded Oscar-season truth squad. Once again, confrontations between an expanding field of reality-based movies and a growing pack of watchdogs, mostly of the armchair variety, have been turning the annual awards ritual into a brutal game of “gotcha.” “Nobody expects a Hollywood movie to be journalism,” a columnist in The Wall Street Journal wrote about “The Big Short” last month in a critique that proceeded to expect just that.

In the lead-up to the Academy Awards — nominations will be announced next week — and Sunday’s Golden Globes, more than a dozen high-profile dramas and comedies have faced factual questions, including “Spotlight,” “Joy,” “The Revenant,” “Concussion” and, of course, “The Big Short.” Depending on the intensity, challenges of this sort can knock films to the back of the Oscar pack, awards strategists say. (It certainly didn’t help “Zero Dark Thirty,” which ran into severe scrutiny in 2013 over its depiction of the C.I.A.’s interrogation tactics.)