"Rocket" Rob Tredwyck was the All-American poster boy, Olympic champion swimmer, and all-around good guy who pitched in around the community and mentored upcoming, younger swimmers. He had connections to U.N.Y.'s swim team through his old coach, Rome, and he was helping another local boy made good, Zach Lindsey, achieve his potential. Kate is attracted to him, hinted when Castle asks why she's staring at Rocket.