This paper examines the practice of “subversive completions (SCs),” whereby one speaker grammatically correct completes another speaker’s developing turn (DT) so as to sap the action of the DT and the ongoing sequence. It displays that SCs may derail or overdo the action in progress, typically for comedic or pestering bias. It also presents three linked turn-taking practices that can be employed to attain subversion and debates the implications of these practices for our grasp of intersubjectivity. Data are in American English, British English, and Russian.