'Black Widow' star O-T Fagbenle says it'd be 'criminal' if he didn't appear in MCU again (exclusive)

Watch: O-T Fagbenle discusses his MCU future after Black Widow

Black Widow star O-T Fagbenle is not done with the MCU yet — and has his sights set on a return to the Marvel fold.

The 40-year-old Handmaid's Tale star plays Mason — known in the comic books as The Agent — in Cate Shortland's blockbuster, serving as an ally for Scarlett Johansson's title character.

The movie finds Natasha on the run after the events of Captain America: Civil War, so she turns to Mason — with whom she seems to have a connection of some kind — to get hold of equipment she can't now find through official channels.

Read more: Johansson happy Marvel waited to make Black Widow

"I had my own story in my head. I write a backstory for every character I do anyway," Fagbenle tells Yahoo Entertainment UK.

"And then when we got into rehearsals, we started comparing notes and came up with a joint idea of it. And I tell you, it's interesting. I can also not tell you anything more than that."

Fagbenle hinted there could be more from Mason in the future in the MCU in order to explore that backstory, with the franchise now frequently spinning off in different directions both in cinemas and on TV.

Read more: Will Florence Pugh return for more Marvel movies?

"I think it would be criminal for there not to be more Mason. That's my perspective," he says.

Fagbenle says he was excited to join the MCU and was relieved when a potential scheduling clash with his music-themed sitcom Maxxx didn't get in the way.

He also confessed that he was impressed and overwhelmed by the depth of knowledge the Marvel fanbase has for the movies.

He says: "I love Marvel movies, but being part of the MCU I have realised that there is a level of fandom... I'm not going to insult them by putting me in that bracket.

"There are like three levels above me. And I love Marvel movies, so that's just a testament to how much Marvel movies are loved."

Read our full interview with O-T Fagbenle, in which he discusses his acting career on The Handmaid's Tale and Doctor Who, working with Scarlett Johansson and the small matter of playing President Barack Obama...

Yahoo Movies UK: We know how secretive Marvel is. Was it a bit cloak and dagger even getting this role? Did you know what you were auditioning for?

O-T Fagbenle: Sometimes they give you fake sides, but I don't think that's what happened. I was given sides for another whole character. I think they were going a different direction and somewhere along the journey they changed their mind about what they wanted in the movie and what they wanted with me. And I'm not gonna fight people about that. That's how it went down.

What was tough was, at the same time, I was making my heart, my pride and joy: Maxxx. There was a point where I wasn't going to be able to do both Maxxx and Marvel, so that was the challenging part. Luckily it all worked out because, otherwise, I would cry.

What was your level of fandom with the MCU before? Did you know everything about it or were you learning on the go?

I'll say this. I love Marvel movies, but being part of the MCU I have realised that there is a level of fandom... I'm not going to insult them by putting me in that bracket. There are like three levels above me. And I love Marvel movies, so that's just a testament to how much Marvel movies are loved.

As someone new coming into the MCU, how useful was it to have Scarlett there as someone who has been in it almost since day one?

I would say it's always useful to have Scarlett Johansson around. What's the situation where you're not gonna be like: "It'd be useful to have Scarlett here, wouldn't it?"

At the end of the day, it's still just people talking to each other and characters talking to each other, which is what I've done as an actor for most of my life. So when you get down to the bare bones of it, it's useful because she's a great actor. And also, why not have Scarlett Johansson around?

We get the impression watching the movie that your character has some history with Natasha. Did you have a backstory in your head for that was, as we never find out in the movie?

Yeah, I had my own story in my head. I write a backstory for every character I do anyway. And then when we got into rehearsals, we started comparing notes and came up with a joint idea of it. And I tell you, it's interesting. I can also not tell you anything more than that.

One of the other characters you're able to spend time with is Florence Pugh's character. She's on this incredible, stratospheric rise to stardom, so what was it like to spend time with her while she's really ascending to the A-list?

That second part isn't really relevant to me, but the relevant part to me is that she's a really kind, generous, loving, conscientious, intelligent, funny person and being around her is a hoot. But she also cares about the world and wants to make changes. I have this charity, The ABC Foundation, and she came and did an Instagram Live around it. She's just such a generous person.

You've been in Handmaid's Tale for several years and now you've done this. Handmaid's is as big as TV gets and this is as big as movies get. How do the two experiences compare?

It's funny. The thing of something being "big" is what happens after I've done the thing that I do, which is do acting with other people and try to create drama. I feel quite divorced in a way from that thing that happens after the work. In a way, the work is the same if I'm doing a play in some East End theatre.

The work is just finding another artist and trying to tell a story together and it's the thing that happens after which is this big brouhaha. I try to keep distanced from that as much as possible because I think it's distorting to one's sense of reality.

On that note, you came up through your stage work and then all of these stalwarts of British TV you've been a part of, like Doctor Who for example. How important are those things for giving you a grounding for when you move into stuff like this?

In a way, if I think of it like "how is it important for that to give me a grounding for this?", obviously it's everything. It's experience and we live in a kind of linear time anyway, so what happened before is relevant to what happens next.

But I try as much as possible just to think that this moment is valuable. This moment with you is valuable, in itself. It's not valuable because at some point someone might watch it and give me a job. I hope that happens as well, but it's also valuable just because we're two human beings having this moment together. I think for me each moment of my career has had its own inherent value.

You mentioned earlier that you have come up with a backstory and, in the MCU, there's always an opportunity that you might be able to come back. Is that something you've had conversations about, seeing more of Mason in the MCU?

Look, I think it would be criminal for there not to be more Mason. That's my perspective.

Mason. A limited series coming to Disney+. 2022.

Put it out in the universe, brother. Put it out in the universe.

Before I let you go, I have to very briefly ask about Obama [in HBO series The First Lady]. Obama, with Viola Davis, as Michelle. What was that like? I assume you've done it or you're halfway through it.

I just finished last night. I did my last scene yesterday with good old Queen V. It's stressful, to be honest, but it was also so fulfilling because Viola Davis is one of the most remarkable people I have ever met.

Getting to spend time with her and her family — her partner Julius [Tennon], who is also her producing partner — being able to be part of that was very life-changing for me.

Black Widow is in UK cinemas from 7 July, or order it on Disney+ with Premier Access from 9 July.