Unit Death Lotto

kate stewart has been noticing people after people winning the lottery than a week after they drop dead for this tough case for unit to crack she's going to need sam shirley mel josh osgood and donna and captain jack harkness on the case who and what is making these deaths happen and why is the doctor not answering when she calls and why is kate seeing ghost of her dad everytime unit rocks up at area 101 is the world ending and can unit fight to save it