AJ Manglehorn is an eccentric locksmith in small-town Texas, who barely engages with community life. He is stuck in the past, consumed with regret for letting his soulmate Clara Massey get away. He continues to write her letters, 20 years after they parted. During one of his regular visits to the bank, Manglehorn allows perky teller Dawn to persuade him to go on a date. This awkward romance helps Manglehorn to come to terms with some of his past failures.