108723
John Alderton took over the role of James and Colin Blakely that of Siegfried , while Lisa Harrow returned as Helen .
 John Alderton, Colin Blakely
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 John Alderton, Colin Blakely