Prince Harry and his fiancee, Meghan Markle, in Nottingham, England, on Dec. 1. (Frank Augstein/Associated Press)

We’re only a couple of months away from the conclusion of what’s turning out to be a real-life Hallmark movie — the May 19 wedding of Prince Harry and American actress turned humanitarian Meghan Markle — and the to-do list items are getting checked off in short order.

The latest revelation: the cake!  Wedding guests may get to feast on a lemon elderflower cake frosted with buttercream, Kensington Palace announced Tuesday. (More on the cake — and yes, there is more to it — below).

Interest in the upcoming wedding is incredibly high, and the content of the guest list (aside from obvious family members) has turned into a big guessing game, full of rumors and clues. Will Harry invite Barack and Michelle Obama? What about Elton John, a close friend of Princess Diana? We know that the Spice Girls all made the cut — Zig-a-zig-whaaa?!

While the royal family has always occupied an outsize place in the public spotlight, Harry is especially beloved by the public. He is fifth in line to the British throne, and his mother, Diana, was the most famous woman in the world at the time of her death in 1997. And his storybook-like romance with an American actress from Los Angeles best known for her role on USA’s “Suits” has captivated the public, both in England and the United States.

Their relationship generated such vitriol that Kensington Palace, in an unusual move, issued a blistering statement denounced racist and sexist coverage when the pair were still dating. (Markle’s mother is black.)

Since announcing their engagement, the couple haven’t been keeping a relatively low profile — they’ve mostly been spotted at charitable events — and on Feb. 28, they appeared for the first time publicly alongside Prince William and his wife, the Duchess of Cambridge.

Here’s everything we know so far about the upcoming nuptials.

When do I need to schedule all of my calendar alerts?

The wedding will take place at noon GMT — meaning 7 a.m. Eastern — on May 19. Set your alarms accordingly.

Where is this shindig?

(If you’re still trying to get yourself invited, probably best not to refer to the ceremony as a “shindig.”) It will take place in St. George’s Chapel at Windsor Castle. The Dean of Windsor, the Right Rev. David Conner, will conduct the service, and the Hon. Justin Welby, Archbishop of Canterbury, will officiate as Markle and Prince Harry make their wedding vows.

Harry was baptized in the chapel, which has also hosted several royal weddings, including those of Queen Victoria’s children and Prince Edward. Here’s a look inside:

How can us common folk catch a glimpse of the royal couple?

If you happen to be in the neighborhood, you may want to park yourself nearby. At about 1 p.m. GMT (8 a.m. Eastern), the newlyweds will hop in a carriage and go through Windsor Town along High Street and then return to Windsor Castle by the Long Walk.

“They hope this short journey will provide an opportunity for more people to come together around Windsor and to enjoy the atmosphere of this special day,” a palace statement reads.

This carriage procession will probably be the public’s best chance to see the two on their wedding day.

I wish to learn more about this cake.

Royal weddings usually mean royal fruitcake, which, gross. Thank goodness this pair is bucking tradition in favor of flavor, because can you imagine actually eating a royal fruitcake during your watch party?

Instead, they’ve asked Claire Ptak, a California-born and now London-based pastry chef, to “create a lemon elderflower cake that will incorporate the bright flavours of spring,” the palace announced. “It will be covered with buttercream and decorated with fresh flowers.”

Markle knows Ptak, having interviewed her before for her lifestyle website, The Tig.  The pastry chef, who owns Violet Cakes in London, “focuses on using seasonal and organic ingredients in her cakes,” the palace announced. “Prince Harry and Ms. Markle are looking forward to sharing the cake with guests at their wedding at Windsor Castle on May 19th.” Geez, how big is that cake gonna be?

Okay, guest list. Who can I expect?

Regular people! Sort of. A lucky 2,640 very vetted individuals will receive invitations to be inside the walls of Windsor Castle on the big day. But many of them will be chosen by the Lord Lieutenant offices. Other guests include neighbors of Windsor Castle, pupils from a couple local schools and people from charities supported by the couple.

Getting inside the chapel, which fits about 800, is another matter. Aside from the obvious royal names (Queen Elizabeth, Prince Charles, etc.), there has mostly been a lot of speculation about potential high-profile guests.

We do know about at least five who made the cut: all of the Spice Girls. That’s according to Mel B, who also coyly in February that she’s attending the royal affair. “I’m going,” she whispered on daytime talk show “The Real” before adding, “I don’t know if I should have said that.” But she isn’t divulging about a Spice Girls performance at the reception; when asked, she threw her hands up in the air and simply said, “I need to go — I’m going to get fired.”

As far as other guests, let the guessing begin! Prince Harry and former U.S. president Barack Obama have hung out a bunch over the years, so lots of folks wonder whether the former first family will attend (and whether that would cause major diplomatic headaches with President Trump). When the BBC asked Harry whether Obama made the cut, he responded: “We haven’t put the invites or the guest list together yet, so who knows whether he’s going to be invited or not. Wouldn’t want to ruin that surprise.”

Serena Williams, who is tennis royalty, is a friend of Markle’s. The Foo Fighters have been mentioned in British tabloids. (The band played at Harry’s Invictus Games in 2014.) And Elton John has rescheduled two shows that originally fell on the wedding weekend. His reasoning? A “scheduling conflict.”

Prince Harry and former U.S. president Barack Obama pose with an athlete at a wheelchair-basketball event during the Invictus Games in Toronto on Sept. 29. (Mark Blinch/Reuters)

What else is happening?

Yes, they’re following a lot of traditions, but this won’t be a stuffy wedding.

“It will be a moment of fun and joy that will reflect the character of the bride and groom,” their spokesman has previously said. “The couple of course want the day to be a special, celebratory moment for their friends and family. They also want the day to be shaped so as to allow members of the public to feel part of the celebrations too and are currently working through ideas for how this might be achieved.”

After the ceremony and carriage procession, the couple and guests will head to St. George’s Hall for a reception. Later that night, Prince Harry’s father, the Prince of Wales, will host a private reception for the newlyweds and their close friends and family.

What’s left on the to-do list? Can I help?

So Markle has already been reportedly baptized and confirmed in the Church of England in a private ceremony, according to the Daily Mail. She attended Catholic school as a child and identified as Protestant.

Royal officials had previously said Markle also intends to become a British citizen.

“We’re pretty tied up with planning a wedding at the moment,” Harry said at a Royal Foundation event in February. Still planning! But the palace has confirmed that the royal family will cover the costs of the wedding. And, E! News reported that Markle already had a bridal shower.

So, no, you can’t help.

A dramatized version of this love story is relevant to my interests. Anything out there for me?

Why, yes! Production began in February on a Lifetime original movie, “Harry & Meghan: A Royal Romance,” starring Murray Fraser and Parisa Fitz-Henley. It’ll air May 13  — just before the big day. Here’s a teaser to hold you over:

This post, originally published March 1, has been updated.