The Undertaker is coming back - as a feature film! Mike Müller slips into the role of Luc Conrad for the last time and investigates a mysterious murder case with his crew in a familiar manner. In his new life, Luc Conrad runs a restaurant in Costa Rica. He travels to Switzerland to celebrate her 70th birthday with Erika Bürgisser. His old companions Fabio Testi and the two Aargau policemen Anna-Maria and Doerig are of course invited to the celebration in an old, run-down hotel in the Engadine. Just as everyone gathers in the garden for the celebration, the hotel director dies under mysterious circumstances. For the Graubünden cantonal police officer Cavegn, it is clear that it was an accident. But the mortician's family suspects, based on the dead man's last words, that it was a murder and extends their stay.