local allowCountdown = false
function onStartCountdown()
    if not allowCountdown and isStoryMode and not seenCutscene then --Block the first countdown
        setProperty("camGame.visible", false)
        setProperty("camHUD.visible", false)

        runTimer("lowEnd", 1, 1)
        allowCountdown = true;
        return Function_Stop;
    end

    setProperty("camGame.visible", true)
    setProperty("camHUD.visible", true)
    return Function_Continue;
end

function onTimerCompleted(tag, loops, loopsLeft)
    if tag == "lowEnd" then
        startVideo('test'); --your file's name
    end
end