Tom Hiddleston has begun filming on
, describing Kiwi director Taika Waititi as "brilliant".
He said: "It's amazing to be back, amazing...it's so much fun, because I haven't played the character for three and a half years and the script is brilliant, Taika Waititi is brilliant," he says.
"It's just the best fun. It is like seeing an old friend again."
To celebrate his return to Thor, the 35-year-old actor has joined Instagram and posted a picture from the set, captioning it: "He's back!"
And hilariously, his Avengers co-star Robert Downey Jr welcomed him to the social media site by poking fun at the now famous "I love T.S" shirt Hiddleston was snapped wearing on holiday with girlfriend Taylor Swift.
He wrote: "Join me in welcoming the biggest T. Stark fan of them all to Instagram", referencing his Avengers character Tony Stark aka Iron Man.
Hiddleston's personal life has been thrust into the public eye as of late after it was revealed he is dating Swift.
But when asked if the focus on his personal life bothers him, he said: "I don't know, it comes down to being authentic.
"Everything you do you have to make sure you truly believe in it and as long as you know that, it doesn't matter what anyone else says about it because the nature of being a public figure is that everyone will have an opinion about anything you do, and as long as you know why you've done something and you've committed to it with authenticity then you're OK."
-Bang! Showbiz with NZ Herald