David Plummer first competed at Olympic Trials in 2004, placing 9th in the 100 backstroke, .02 out of making the final. That fueled him to make the final in 2008, which he did, placing 7th. In 2010, Plummer finally had his moment, winning U.S. Nationals and making the 2011 World Championships team.

When it came time for the 2012 Olympic Trials, Plummer finished an agonizing 3rd in the 100 backstroke final, .13 out of being an Olympian. After those trials, Plummer took some time to find himself and traveled around. He would ultimately make a return at the 2013 U.S. Nationals, making the team and finishing with a silver medal in Barcelona in the 100 backstroke final. Plummer would come into the 2016 Olympic Trials as a favorite to make the field among a stacked field of competitiors. In semi-finals of the 100 backstroke, he would make a statement, swimming a 52.12 to claim the top seed and close in on Piersol's legendary World Record mark at the time. In finals, Plummer would finish 2nd to Murphy, making the U.S. Olympic team at age 30 and as a father of 2. The oldest First Time Olympian in U.S. Swimming History, Plummer would win bronze in Rio, behind Ryan Murphy and Xu Jiayu. He'd also come away with a gold medal in the 400 medley relay for his contributions in the heats.

Following the Olympics, Plummer would go quiet into retirement, the dream fulfilled and with new family challenges and happy memories awaiting him.