Good Luck Earth
by John McKenna
A time traveller from the 36th century rescues a man from the late 20th century from certain death and thrusts him into the future. Together they must defeat the Siren, a devious and beautiful time manipulator from an alternative future. She has sent a comet hurtling towards a defenceless Earth. In total defiance of all logic a huge neon sign is attached to the comet - Good Luck Earth.