It is not due to Thekla Reuten and the character Tessa. Both aspects should be enough for an entertaining series. However, it is just a little less than entertaining. Tessa should have improved and developed Rita. Because what is missing in Rita, Tessa also misses. While so much can be done with it ...
Series that started very well and started bleeding to death after episode 4. Tessa is now (after episode 8) written very far into the corner to my taste. Hopefully it will be okay :-)