In a saucepan over medium heat, combine sugar and corn syrup. Stir until sugar is dissolved. Remove from heat and stir in peanut butter until smooth. Add crispy rice cereal and mix well. Press the mixture into a greased 9x13 inch pan.
In a microwave-safe bowl, melt chocolate and butterscotch chips together, stirring every 30 seconds until smooth. Spread over the cereal mixture in the pan. Let cool and set before cutting into bars.