It opens with Jai (Santhosh) rescuing Ajith (Rajendran), Shiva (Jeeva), Mani (Jagan) and Raj (Bharani) from the Sri Lankan military and bringing them safely to India. We are told that Jai was in the island nation searching for his in-laws and had left his pregnant wife, Lekha (Reshmi) to look for them. He takes them to his house, that exists in the middle of a water body. They are welcomed by the Lekha, who has now delivered a male child. However, eerie happenings in the place convince the friends that Lekha is long dead, and it is her ghost that they are interacting with. They try to warn Jai and save him, but will it be too late for that?
For a horror comedy, Bayama Irukku is short on both scares and laughs. The predictable script hardly displays any inventiveness and is content to assume that anything that Rajendran does will make audiences laugh.