false alarm

详细解释:假警报, 引起一场空喜欢的人(或物)
【计】 误报警

英语解释：

名词 false alarm:

a warning that is given about something that fails to occur

例句：

Martin said the boss was going to make a surprise visit, but it proved to be a false alarm.马丁说老板将来个突然造访，但结果却是虚惊一场。