Currently you are able to watch "Magnum P.I." streaming on DIRECTV, fuboTV, Peacock Premium, NBC, USA Network or for free with ads on Freevee, Peacock, Peacock Premium. It is also possible to buy "Magnum P.I." as download on Apple TV, Amazon Video, Vudu, Google Play Movies, Microsoft Store.
Thomas Magnum, a decorated former Navy SEAL who, upon returning home from Afghanistan, repurposes his military skills to become a private investigator in Hawaii taking jobs no one else will with the help of fellow vets T.C. Calvin and Rick Wright, and the former MI:6 agent Higgins.