This is established in one introductory sequence where he looks out at some futuristic city before traveling to our own era. (entertainmentvoice.com)
An extended introductory sequence ends with a close - up of an eye. (kids-in-mind.com)
Shortly after an awesome introductory sequence in which you test drive both the Lamborghini Centenario and a dune buggy, a character select screen appears and you're given the ability to choose 1 of 14 different boss representatives of various genders and ethnicities. (thekoalition.com)