O filos mou o Lefterakis (Greek: Greek: Ο φίλος μου ο Λευτεράκης, Alternate translations: My Friend, Lefterakis or Lefterakis, My Friend) is a 1964 Greek theatrical comedy film starring Dinos Iliopoulos, Kostas Voutsas and Maro Kontou.
Thodoros (Dinos Iliopoulos) and Fofo (Maro Kontou) are a married middle-class couple, stuck in a rut. Thodoros has "invented" an out-of-town friend, Lefterakis, who is conveniently in Athens every time Thodoros wants to have a night out with his mistress.
One evening, while in the middle of a card game with his friend Thanassis (Giorgos Konstantinou), he starts explaining his scam to him. However, they are interrupted by the maid, who announces that Lefterakis has just arrived from Patras. Fofo, apparently oblivious to her husband's horror and Thanassis' confusion, invites Lefterakis (Kostas Voutsas) to spend a couple of days at their place.
Over the next couple of days, Thodoros is becoming more and more paranoid, as he first suspects that someone is playing a prank on him, then that he's being blackmailed and, as the fake Lefterakis seems to know a lot of details about him, that he's indeed losing his mind.
In the end, it is revealed that Fofo has known about Thodoros' infidelities, and the invention of "Lefterakis" for a while. Fofo has planned the whole thing to teach him a lesson, asking a friend to impersonate "Lefterakis". The couple finally decides to put their differences aside when Fofo announces she's pregnant.