"Vampire Diaries" Season 5: Stefan rescued by whom exactly?

The Vampire Diaries Season 4 DVD: Stefan at the end of Part One rescued by whom exactly? Save his people ...... new role Tessa (Janina Gavankar). Why would she save Stefan? It is not known, but she seems to Stefan "too bloodthirsty" surprised. In this week's new focus, the audience will see through the lens Tessa and Stefan recalls the past, Tessa's real purpose may be exposed. At the same time, Tessa will be a disturbing news to Damon.