"The thing I noticed about Jack was when we did a reading of the script, just to warm up"

Amanda Peet is talking about her experience with Jack, a fellow star. She noticed something special about him when they did a reading of the script together. This was likely a warm-up workout to get into character and practice their lines. It appears that Jack had an unique talent for the craft of acting. He had the ability to bring the script to life and make it feel real. His performance was so remarkable that it left an impression on Amanda Peet. She had the ability to acknowledge his talent and value his skill. This quote is a testimony to Jack's skill and Amanda Peet's adoration for it. It is a reminder that talent and effort can make a distinction on the planet of acting.