open on

open on (something)

To begin with some specific thing. The panel discussion opened on a debate about the proposed tax reform legislation. The film opens on a shot of the hero looking out over the valley at dusk.
See also: on, open
Farlex Dictionary of Idioms.

open (out) on(to) something

[for a building's doors] to exit toward something. The French doors opened out onto the terrace. The doors opened on a lovely patio.
See also: on, open
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.
See also:
  • open on (something)
  • open into
  • open into (something)
  • nitty-gritty
  • nitty-gritty, the
  • hero of the underworld
  • reach an understanding
  • captive audience
  • reach a conclusion
  • work up to