this anniversary special be quite interesting a it feature excellent performance from all involve . the natural chemistry of patrick troughton and nicholas courtney for instance be one of the truly shin element of this production . also richard hurdnall do a remarkably good and under rat version of the 1st doctor . it be most interesting to see the 1st doctor pair up with tegan a they both have intense ego which work brilliantly in tandem . meanwhile we have the familiar coupling of the 3rd doctor and sarah jane along with just strange choice turlough and susan . this adventure capture the spirit of doctor who at it fine and and be quite well write and act and and execute for an anniversary special .