Auf Wiedersehen Pet (1983)

The lads go off for a weekend's fishing in the country, where they meet up with an English hitchhiker who is very mysterious, they lads suspicions grow when he later runs away from the police. However after a large confruntation the lads find out the truth, the boys turns out to be AWOL from the Army. The lads persuade him to do the right thins and return to his unit.