Joss Whedon gives details about ' Avengers ' story . ' Age of Ultron ' centers around a sentient super - robot . `` I knew right away what I wanted to do with him , '' Whedon says . Whedon says it is key part of robot 's personality .
Joss Whedon gives details about ' Avengers ' story . ' Age of Ultron ' centers around a sentient super - robot . Whedon says it is key part of robot 's personality .