STORY LINE (in english):
'In West Berlin on its subway train network construction, Mehmet one of its contractor workers is hit by a bulldozer who's driver supposedly couldn't hear his screams and amid turmoil and fighting amongst some of the the workers there, he succumbs to his injuries right at the scene of the accident. 

The foreman, Mr. Bauler decides not to alert the police otherwise the entire human smuggling ring could be exposed to law enforcement.  The man's body is to be disposed of that night.  But when it is being transported away from the construction site, one leg' appears out of the side of the dumpster and someone who happens to be drunk observes this happening through a faulty part of the fence around the construction area.  Suddenly, the fence breaks with him on it crashing through on to the construction site grounds. Workers warn him to go away.  But, 'he reports what he saw to the police, whereupon commissioner Hans-Jochen Wagner from a "foreigners working group" is assigned to investigate the matter.  They are shown in a classroom looking at a presentation about foreign workers.  

Following a hint, Wagner gets in the car with another policeman and rushes to where he knows the truck may have taken the body and tries to find the alleged body in a gravel pit, digging at the pile himself with one of the sumugglers looking at him, but without success.  No body is found.  One cop seems to recognize a smuggler there named Abdullah, though. The smuggler says: "There aren't enough people.  Also, the police don't have enough people".

Meanwhile, Hassan the dead man's brother-in-law is arrested by the police for fleeing through the streets onto a train platform and jumping into a river.  He was stabbing at someone with a knife for possibly provoking him. 

When the construction site owner Mr. Kaiser found out about it, he was concerned that Hassan might reveal something about the accident, so he had his sister Ayshe involuntarily taken away to a guest house..

Wagner and his colleague senior commissioner Martin Schmidt are in the picture about Kaiser's machinations.'  They drive up to the construction site some time after the accident.  A forman at the site recognizes the policeman named Wagner in the car and he quickly and quietly says "Go down below and close the door!"  A worker then climbs down the ladder and the police even describe what's happening, immediately.  The guy is shown appearing on the ladder beneath the construction area yelling something to the workers.  They, then throw down their shovels and start running to a certain location.

Wagner approaches the manager's trailer.  The manager asks: "Why such an early morning visit?" "Come on out" says the policeman for questioning.
The two cops are still not able to prove any wrongdoing. Wagner 'suspects Kaiser's drug deals. So he wants to use Hassan as bait to track down not only the drug leader, but also Abdullah, the Turkish head of the human trafficking ring.

During prisoner transport operations at the airport, Hassan succeeds in an escape from a police prisoner van, seemingly planned and initiated by Wagner. Hassan runs from truck to truck during the escape. 

After the escape goes off as planned, the three cops toast to celebrate. Hassan is not only secretly pursued by the police, but one of Kaiser's men is on his heels, too.  Since he wants to hide with his sister and yet cannot find Ayshe in her apartment, he starts looking for her.  Hassan finds and is able to overpower Abdullah.  And tries to force him to say where his sister is.  He just leaves him in the meat refrigerator.

It is already clear to him that only Mr. Kaiser can be behind her disappearance.  Hassan finds Kaiser's house.  The green Chevy Corvette is parked out front.  He is chased by dogs.  Hassan can calm one of the dogs, but the other one runs up and attacks after he falls off of the car's rooftop.  He then climbs into a tree away from the dogs and escapes over the fence. Hassan does not manage to get to Kaiser 'because his property is too well guarded.   

Later, Hassan is in group home nursing his wounds and he is found unnoticed by one of Kaiser's pals who gets on a pay phone and makes a call about him and his whereabouts. So, Hassan now bandaged up goes to the place where Mehmet - his brother-in-law.was buried to pray there.  'This way, the commissioners who are also still following him finally secretly learn of the hiding place where the body, his brother-in-law is buried.

He is found again unnoticed by Kaiser's friend who finds him next to a train platform, draws away his attention quickly and pushes Hassan in front of a train railway, but fortunately he can save himself and survive.  The plain-clothed police officer is blamed and attacked by by-standers. 

Meanwhile, Hassan is able to overpower the assassin and force him to take him to his sister.  She is now forced to work as a prostitute in the brothel', only 'disguised as an inn , and is currently defending herself against an intrusive suitor. One of the employees there calls the police.

Meanwhile, senior commissioner Wagner and his people actually find Mehmet's body. 

Commissar Schmidt arrives at the inn in a green car and tries to contact Hassan who is armed and with his sister Ayshe and holding the client hostage amid terrible interference coming from so many bystanders.  Meanwhile, one brothel operator runs to Kaiser and Abdullah in a waiting car outside and she describes what's going on and she gets right back out of the car.  Then, they drive away and get word out trying to plan something like impersonating the police.  The police try' to get Hassan to give up the hostage and they try to say that they will satisfy his demands like guaranteeing him safe passage 'to Turkey.  Meanwhile, Hassan doesn't trust the police and so he eventually goes downstairs and tries to escape along with his sister and the hostage. Then, Hassan is killed by a bystander. '

SOURCE: (updated)-- Wikipedia Germany, Wikipedia the free encyclopedia
      https://de.zxc.wiki/wiki/Tatort_(Fernsehreihe)#Liste_der_Tatort-Folgen
      (see: 'Main article : List of crime scene episodes')