Mouse Overboard # 62 : Book Paperback (Geronimo Stilton)

Geronimo Stilton and family, were invited to Lisbon, Portugal, to retrace the journey of the great explorer Vasco da Gama. He was the first European to reach India by sea — and was apparently an ancestor of the Stiltons! But once they got on the boat, they learn that someone was trying to sabotage the voyage. Could he figure out who?