We have 8 travelers:
– 1 criminal,
– 1 police man,
– 1 mother with her 2 daughters,
– 1 father with his 2 sons  (2 different families).

• The mother wants to kill the 2 sons,
• the father wants to kill the 2 daughters
• The criminal wants to kill everybody

• The criminal can’t kill anybody if the police man is present.
• The mother can’t kill the sons if the father is present,
• the father can’t kill the daughters if the mother is present.
• The police man will not prevent the mother or the father from killing any of the children.

All eight travelers arrive at a river at the same time. They want to get across. However, there is only one boat, which can take maximal two people. The boat can only be navigated by an adult.

How can you get all eight people across the river, without anybody getting killed?