The Silken Affair (1956)

Spoiler: Roger Tweakham, a married accountant leading a humdrum life, gets involved with a motivating model, tweaks the books of a stocking factory whose owner he likes so it will show a paper profit and stave off bankruptcy. He then juggles the books of a rival firm whose owner he detests, to show it, on paper, teetering on the edge of ruin. His book-cooking is soon discovered, but by buying the stocks of the first one and then the other, he finds himself in control of both. After a tangle with the law and a farce of a trial, he takes over both operations, merges the two, with the former owners as his partners, kisses the model goodbye and returns to his unsuspecting wife.