杀戒 (The show is here: 杀戒(电影))
生活在小城里的美丽姑娘江月娥（倪妮 饰）刚刚经历过感情失败，却与高大帅气的肖立昆（刘烨 饰）偶然邂逅，二人一见钟情.因为一个突发状况，肖立昆与江月娥闪婚成为夫妻，并生下儿子肖磊.婚后夫妻之间出现了无法弥补的感情裂痕，肖立昆对于娇妻婚后的种种行为疑心重重，而江月娥亦有重大婚前隐情瞒着肖立昆. 在确认江月娥出轨后，两人毅然决定离婚，但江月娥不放心儿子继续跟肖立昆在一起，誓死争夺抚养权，肖立昆也毫不让步，决心守住自己的孩子.夫妻为儿子对簿公堂各施手段，江月娥突然在法庭宣称肖磊不是肖立昆的骨肉，要求做DNA亲子鉴定.目睹事件全过程的王晓娟（张逗逗 饰）来找肖立昆，道出肖磊出生的真相.精神重创之下，肖立昆回老家取出祖传的杀猪刀......
In the end, the cuckooed guy decided not to kill his wife and lover (sorry ... spoiled your surprise).
For me, if this event ever happen to me. I wouldn't be so kind. There are simply too many ways to employ tact to kill off the offending joker. I am a lion and shall remain so. Live by the sword, die by the sword. It is therefore always a choice not to play other guy's women, no matter how pretty. Choose the next unattached brand new sweet young thing.
The researchers also noticed that mother fairy-wrens will teach the password to other caregivers of her young, including mates and other helpers. When they do this, however, they're out of earshot of the chicks. Which is smart. They also noticed that the signature element varies from nest to nest; all passwords are unique and tied to a particular mother. Cross-fostering experiments confirmed that a fairy-wren mother will not feed a genuine fairy-wren chick if it doesn't know the password.
This is a very sad case of a stable and reliable beta male made unwittingly to take care of another alpha male's offspring. So read the book: Sperm Wars by Robin Baker and learn well.