fever pitch 
noun [mass noun]
A state of extreme excitement: the football crowd was at fever pitch [in singular]: a fever pitch of nervous excitement...
- Excitement was at fever pitch for the final divisional game against St. John's (Belfast).
- Excitement reached fever pitch when Tony Convery was yellow carded and Antrim had used up their 6 subs with ten minutes still to go.
- Excitement reached fever pitch as Santa took centre stage on Saturday in the company of a group of delighted and excited children.