Ah, the man to transcend genres. Sir Ian Mckellen covers both our science fiction and fantasy bases, he even dabbled in horror a wee bit. The Keep in 1983 and Apt Pupil in 1998. But he is, of course, most well known for playing Gandalf in the Lord of the Rings franchise and Magneto in the X-Men franchise.
And of course, there may be nothing better than his friendship with another legend, Patrick Stewart.
McKellen has been open about his sexuality since 1988 and to this day, champions LGBTQA+ social movements. He co-founded Stonewall UK, which lobbies for legal and social equality.
He is both an incredible actor and an important activist.