What is ace in the hole?

"Ace in the Hole" can refer to a few different things depending on the context:

1. Film: "Ace in the Hole" is a 1951 film directed by Billy Wilder, starring Kirk Douglas. The movie is a drama about a cynical, down-and-out reporter who exploits a mining accident to try and revive his career. The film is a critique of media sensationalism and the morality of journalism.

2. Music: "Ace in the Hole" is also a song, most famously known in its version by George Strait. The song emphasizes the importance of having a secret advantage or fallback option.

3. Phrase: In a more general sense, an "ace in the hole" is an idiomatic expression referring to a hidden advantage or resource kept in reserve until needed. The phrase originates from poker, where having an "ace in the hole" is considered a strong advantage due to its high value.

4. Literature and Pop Culture: The term can be found in various works of literature and pop culture, often used in contexts that pertain to strategy, gaming, or hidden talents.

If you have a specific area or context in mind, let me know, and I can provide more detailed information regarding that particular reference to "Ace in the Hole."