[sit] up and [take] notice
1
to suddenly become attentive or alert, often due to something surprising or remarkable
- She is sitting up and taking notice of the speaker's words.
- The loud crash made everyone in the room sit up and take notice.
- The new policy changes really made employees sit up and take notice.
- They were sitting up and taking notice of the beautiful sunset when the phone rang.
- His exceptional performance in the competition caused everyone to sit up and take notice.