A cab driver goes to pick up a passenger and visits his apartment. Someone rings the door bell and then fires a gun through the door, injuring the driver.
A bank robbery happens right under Derrick's nose. One of the customers tries to stop the robber, but he gets injured and the robber barely manages to escape.
A man, sentenced for life for a goldsmith's murder, is released after 15 years. The cop who arrested him back in the day, is bothered by a hunch that this may not be the guilty man after all.
Derrick is making good recovery of his wounds, but he can't return to work yet. Meanwhile, Harry is asked to help an older cop in his investigation. Several girls have been murdered in a small neighborhood, but no progress has been made, so the police finally decide to use a decoy.
Dr. Winter is shot in his laboratory. Some of his coworkers say they saw Dr. Römer enter the building the night. However, Dr. Römer has been dead for three months.
