bàn lù shā chū gè Chéng Yǎo jīn
lit. Cheng Yaojin ambushes the enemy (saying)
fig. sb shows up unexpectedly and disrupts the plan
sb whose presence is regarded as irksome
bàn lù shā chū de Chéng Yǎo jīn
see 半路殺出個程咬金|半路杀出个程咬金[ban4 lu4 sha1 chu1 ge4 Cheng2 Yao3 jin1]
Chéng Yǎo jīn
Cheng Yaojin (589-665), aka 程知節|程知节[Cheng2 Zhi1 jie2], Chinese general of the Tang dynasty