Expression: Sauver la mise

Meaning: To save the day

Literal translation: To save the stake/ante

Notes: The French expression sauver la mise has both literal and figurative meanings. Literally, it means to pull out one's ante or stake, so while it's no longer possible for you to win big, neither are you at risk to lose your stake. Figuratively, it means to get someone out of a tight spot. Unlike many expressions, this figurative meaning is very logical, if you consider the literal meaning and assume that you would have lost had you not pulled your money out.
Example:
J'avais des ennuis, mais mon frère m'a sauvé la mise !
I was in trouble, but my brother saved the day!