Simplify the following text for a Grade 9 native English-speaking person.
Original: Afterwards , Peter Pratt and Geoffrey Beevers played a physically decayed version of the Time Lord until Anthony Ainley assumed the part in 1981 .
Simplified: Afterwards , Peter Pratt and Geoffrey Beevers played a decayed version of the Time Lord , until Anthony Ainley assumed the part in 1981 .