Tom Hiddleston and Swifty fans alike were delighted this week when Tom joined Instagram.
But no one was more delighted the Robert Downey Jr. He played a little joke on his Marvel co-star that we're sure he's been waiting ages to do.
Mocking Tom's 'I <3 TS' top, Rob shared the picture and said: “Join me in welcoming the biggest T. Stark fan of them all to Instagram! @twhiddleston.”
But now, Tom has had his say on the whole thing.
"Robert and I are very close and I got to know him working on the Avengers in 2011," he told the LA Times.
"There's a lot of mutual affection. I feel like it's an expression of mutual admiration. It's great. He's very sweet."
Tom added: "And within the Marvel universe there's a lot of that going on – a lot of throwing paper aeroplanes."
However, Robert took his love even further yesterday. Just look:
(Tom's first IG photo was of him dressed as Loki).
These lads the bomb.