lo and behold
US /loʊ ənd bɪˈhoʊld/
UK /loʊ ənd bɪˈhoʊld/

1.
不料, 瞧
used to present a new and surprising event, often a sudden appearance
:
•
We searched everywhere for the lost cat, and lo and behold, she was sleeping on the couch the whole time!
我们到处寻找丢失的猫,不料,她一直睡在沙发上!
•
He opened the old chest, and lo and behold, it was full of antique coins.
他打开了旧箱子,不料,里面装满了古董硬币。