Fluent Dysphasia (2004)

Starring Academy Award Nominee Stephen Rea as Murph, who has little to say to his teenage daughter. He wakes one morning after a drunken night out, to find that he can only speak fluent Irish, something he could never do before, and that he has completely forgotten how to speak English. The situation leads to genuine, if unorthodox, communication between father and daughter. There's nothing funny about fluent dysphasia...