Mark Ruffalo and Scarlett Johansson share birthdaysAvengers official Facebook

Mark Ruffalo and Scarlett Johansson both share their birthdays and this year, it also happens to be the day of Thanksgiving. Both actors share excellent chemistry playing superheroes in the Marvel Cinematic Universe and this off-screen friendship is clearly evident with the way their on-screen characters play out as the Hulk/ Bruce Banner and Black Widow.

Johansson turns 34 this year and Ruffalo turns 51, reports comicbook.com, but their interactions rarely seem like there's a 17-year gap between the two stars. While great actors like themselves could easily pull off good chemistry on screen, their friendship even otherwise is heart-warming.

Black Widow calms the Hulk down in Avengers: Age of UltronAvengers official Facebook

Johansson and Ruffalo first started working together in Avengers (2012). The first meeting between Romanov and Banner is set in India when we were first introduced to Ruffalo as the Hulk as well.

By the time the second Avengers movie came along in 2016, the two characters had almost-there romance. The love that the two share is pretty strong in the movies as Black Widow is pretty much the only person who could calm the Hulk down back into Bruce Banner, in fact the scene in Thor: Ragnarok where Hulk turns into Banner after two whole years just because he hears her voice is quite touching.

Scarlett Johansson as the Black WidowAvengers official Facebook

While both characters survived Thanos' "dusting" in the last movie, their fate is still in the balance as far as Avengers 4 is concerned.

Scarlett Johansson does not have any social media, but Mark Ruffalo posted a quick message for those celebrating Thanksgiving with this tweet.

As for the future projects of both actors, Johansson is reported to be working on Taika Waititi's Jojo Rabbit, a story about a Hitler youth who finds out his mother has been hiding a Jewish boy in their home. Meanwhile, Ruffalo is working on a film portraying Robert Bilott in his next film directed by Todd Haynes about a lawyer who took the chemical company DuPont to court.

Mark Ruffalo stars as Bruce Banner/ HulkAvengers official Facebook