“Three Stories” is the House M.D. episode that reveals House’s leg injury through three patient stories.
In the season-one finale, House teaches medical students by presenting three cases. The episode initially encourages viewers to treat the cases as separate diagnostic puzzles, but its structure gradually connects the lesson to House’s own past and chronic leg pain.
The story establishes that House suffered an infarction in his right quadriceps muscle and underwent surgery after the injury was discovered. The resulting pain and disability became defining parts of his character and contributed to his dependence on Vicodin.
The episode is notable both for its medical backstory and for its experimental storytelling. It won the Primetime Emmy for Outstanding Writing for a Drama Series, so it is often remembered as both a character-origin episode and an award-winning installment.