Time surfers

"Caleb Fisher is the right-hand to his time-surfer, scientist father, John. Together on their thick metallic ship, they travel at super speed into the past and rescue treasures that have otherwise been lost -- priceless works of art from the torpedoed RMS Lusitania, a crown jewel threatened by a flood in 1216 CE England -- all for the good of humanity and for the glory of the ruling Global Council. But there are rules for time surfers. Never brin...