Sir Ian McKellan and Sir Patrick Stewart are our favorite besties -- and now they want to be BFFs with Taylor Swift and her "Girl Squad" and we can't blame them -- those ladies know how to have fun!

Recently the old pals and X-Men costars gave dramatic readings of Swift's lyrics for NPR's "Ask Me Another" and subsequently tweeted at the singer requesting an entrance in her legendary brood of beautiful babes.

Professor X wrote, "So @IanMcKellen recited Bad Blood and I did Blank Space on @NPRAskMeAnother. May we join the squad, @taylorswift13?"

See the rest of the funny interaction ...