A typical movie is said to have three acts, but this is not a steadfast rule. Film acts are not defined as strictly as play or TV show acts, which are set off with act breaks.

The johnaugust.com glossary explains that “Since screenplays never show act breaks, an ‘act’ is really a theoretical concept. Screenwriters talk about three acts, meaning ‘the beginning,’ ‘the middle,’ and ‘the end.’”

Per Syd Field, it is not uncommon for people to break the middle act in half: act 2A and 2B.