Swing into action
Definition 1 of 1
Pro Tip 1/3Immediate Response
Use this phrase to describe a quick reaction to an urgent situation. 
When the power went out, the technicians swung into action to restore it.
Pro Tip 2/3Active Initiative
It implies taking active steps, not just planning or discussing. 
The community swung into action to clean up the park.
Pro Tip 3/3Not Literal
The phrase is metaphorical; it doesn't involve physical swinging. 
As the deadline approached, the whole team swung into action.