"Who's Minding the Mint? (1967)"
One my favorites as a kid and have seen a few times since. One of those great comedies few people have seen, fantastic cast.
Harry Lucas (Jim Hutton) works at the U.S. Mint in Washington, D.C. He has an admirer in sweet co-worker Verna Baxter (Dorothy Provine), who tries to woo him by giving him home-cooked (but nearly inedible) fudge. Lucas accidentally brushes $50,000 in currency into the bag with the fudge, and walks out with it. Before he realizes his mistake, he disposes of the fudge, simultaneously destroying the currency, and an audit is planned at the mint shortly.
In desperation, he finds someone who will help him get into the mint after hours and print up replacement currency, but learns that he will eventually need a group of people (a safecracker, a person to navigate entry through the sewer, etc.) to realistically pull it off. He finds those willing to help him on the condition that he'll print them a million dollars apiece. The time for the operation is moved up unexpectedly, forcing the group to go in immediately, not completely prepared - and dressed as they are. As the caper unfolds, few things go according to plan.