The Big Bang Theory finale became a hit among fans due to its lack of closure and surprise appearance by Sarah Michelle Gellar. The writers approached Gellar, who gladly agreed to be part of the show she loved. This unexpected moment left the cast stunned, including Jim Parsons, as they delivered their emotional final read. Despite the pressure to end it perfectly, Parsons believed the finale ended in the best way possible. Fans loved that it didn't offer closure but allowed the sense of the friends' lives continuing.