'You are the best': Mark Ruffalo's birthday wish to 'Avengers: Endgame' co-star Robert Downey, Jr. proves that the 'Science bros' share an equally strong bond off-screen

From Sherlock to Iron Man, Robert Downey, Jr. has never failed to mesmerise viewers with a charismatic performance. w, as he turned 54 years old on Thursday, April 4, his 'Avengers' co-star Mark Ruffalo extended heartwarming birthday greetings to actor. He took to Instagram and shared an orable picture where Downey can be seen planting a kiss on his cheek.

In post, ' Hulk' wrote, "Happy Birthday, @robertdowneyjr! Thank you for your kindness, leership, and generosity for all 50 years. You are best 💚"

Here's post:

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Kwn as  'Science Bros' in Marvel Cinematic Universe, Tony Stark aka Iron Man played by Downey and Bruce Banner aka Hulk played by Mark Ruffalo share a very strong bond on screen and seems like bond is equally stronger off-screen as actors are often seen engaging in hilarious banters on social media.

Meanwhile, Marvel superheroes are all set to pair up yet again for  fourth and last venture of 'Avengers' franchise titled 'Avengers Endgame'. much-awaited film is all set to hit big screens on April 26, 2019. 

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It is 22nd instalment in Marvel Cinematic Universe. flick brings toger all Marvel superheroes, played by actors including Robert Downey Jr., Chris Hemsworth, Mark Ruffalo, Chris Evans, Scarlett Johansson, Benedict Cumberbatch, Don Chele, Tom Holland, Chwick Boseman, Paul Bettany, Elizabeth Olsen, Anthony Mackie, Sebastian Stan, Letitia Wright, Dave Bautista, Zoe Saldana, Chris Pratt, Jeremy Renner, Evangeline Lilly, Jon Favreau, and Paul Rudd. In fact, Oscar-winning actress Brie Larson who debut in MCU as Captain Marvel recently will also be a part of  film. Meanwhile, actor Josh Brolin will also resume role of Thas in upcoming venture following 'Avengers Infinity War'.

'Endgame' is a direct sequel to 'Infinity War' from last year. Directed by Russo Brors, film is all set to release in India on April 26, 2019.