It's set to be their most explosive interview ever, with no topic off-limits and nothing left to lose for the royal couple.

As Meghan and Prince Harry's much-anticipated Oprah Winfrey prepares to air in the US today, many will be wondering how to watch here, and just what on earth they are in for.

While the timing has been slammed as Prince Philip remains in hospital, it's unlikely to deter viewers, with the interview one of the most anticipated celebrity interviews of recent times.

So how can you watch and what can you expect? The Herald has you covered.

How to watch and where to go

It was last week revealed where we can watch the full interview here in New Zealand.

Discovery NZ has secured the rights to air the CBS interview tonight at 8pm ET (2pm NZ), and it will play on Three and Three Now at 7.30pm on Tuesday, March 9.

The Herald will bring you full in-depth coverage following the airing of the interview, with Kate Hawkesby breaking down the interview and likely fallout for the previously golden couple.

What you can expect to see

According to CBS, the focus of the interview will start solely on Meghan before bringing Prince Harry in for further insights.

Sneak peeks of the interview released over the past week have given fans a taste of what to expect from the interview where "no subject was off-limits".

"You've said some pretty shocking things here," Oprah told Meghan Markle in the first sneak peek of the tell-all interview.

Harry shared his biggest fear was "history repeating itself", a reference to what happened to his mum, the late Princess Diana.

"I am just really relieved and happy to be sitting here, talking to you, with my wife by my side," Harry said in a clip released by the network. "Because, I can't imagine what it must have been like for her going through this process by herself all those years ago because it has been unbelievably tough for the two of us, but at least we have each other."

Oprah can also be seen asking Meghan: "Were you silent, or were you silenced?"

Meghan is also seen hitting out at royal restrictions and claiming "there is an active role that the Firm is playing in perpetuating falsehoods about us".

The duchess is also expected to finally expose her rift with Kate Middleton and discuss the estranged relationship with her father, Thomas Markle.

The couple are also set to speak about their move to the United States and their "future hopes and dreams for their expanding family".

Why Oprah and why now?

The timing of the interview has been slammed by critics with Philip still in hospital following a lengthy stay and a heart procedure.

Harry and Meghan were urged to delay their Oprah tell-all in light of his condition.

Royal sources said the family was "pretty appalled" that the Oprah interview was still going ahead while Philip remains in hospital.

Now royal commentators are calling for the interview to be shelved until Philip recovers.

Author of Prince Harry, Brother, Soldier, Son Penny Junor said, "It's bad timing when they're going to be saying, 'Poor us'."

Meanwhile, another royal source asked, "Why are they doing it?" and others questioning why Oprah?

According to sources, the couple were waiting for the right person and that right person came in the form of the couple's friend and neighbour Oprah.

The talk-show queen revealed in a clip that she has been chasing the interview with the couple for years, well and truly playing the long game after attending the couple's 2018 Windsor Castle wedding and befriending Meghan's mother Doria.

Oprah has also previously promoted Clever Blends, a herbal tea and coffee company Meghan invested in - sharing an Instagram video of a gift basket she received from Meghan.

The fallout

The couple's fallout with the royal family has been widely publicised, but thus far it's mostly been speculation.

However, with Harry and Meghan looking likely to confirm rifts within "the firm" we are likely to see the two lose more than they have before.

Harry and Meghan Markle risk losing their titles as Duke and Duchess of Sussex for breaking their Megxit deal with Sunday night's Oprah TV tell-all, according to reports.

Royal courtiers met last week to discuss stripping the couple's titles and tearing up the "Sandringham summit" agreement made a year ago involving their exit from life as senior royals, sources told the Times of London.

"I don't think that after this interview, anything is off the table, to be honest," one source in the royal household told the UK paper, referring to the potential stripping of the pair's titles.

Such a move would be "a big step," the source conceded — stressing that it highlights how "cheesed off" the Queen is over the "circus" around the Oprah Winfrey special.

However, another source close to the Queen confirmed palace discussions but insisted that "the titles are not up for debate", the Times stressed.

One source said, "The response will depend very much on if they go after the institution or the people" in the royal family.

"If they go after the people, the people will come out swinging. The institution can take the blows, the people cannot," the source said.

"The institution is not at war, the Sussexes are at war."

• CBS presents Oprah with Meghan and Harry will broadcast Tuesday, March 9 at 7.30pm on Three."