The theme is “America United,” but Covid-19 and the specter of domestic terrorism are casting shadows over the event.

Joe Biden will be sworn in as the 46th president of the United States on Wednesday in a ceremony that will keep with tradition while being unlike any other inauguration in U.S. history.

There will be pomp, ceremony, former presidents, congressional leaders, A-list performers, parades and tributes to the troops — but before a small, socially distanced audience in a city that has been locked down because of the dual threats of the coronavirus pandemic, which has killed over 400,000 people in the U.S., and possible domestic terrorism after the deadly violence at the U.S. Capitol.

One thing there won’t be is an argument that Biden will have drawn the biggest crowd in inauguration history — he and officials in Washington, D.C., hope it will be the smallest, with people watching from their couches instead of the National Mall.

The day’s events will be far more star-studded than Donald Trump’s inauguration, which was headlined by country singers Toby Keith and Lee Greenwood. Among those participating Wednesday are pop superstars Lady Gaga and Jennifer Lopez, rock icon Bruce Springsteen and country superstar Garth Brooks.

Here’s what to expect Inauguration Day — and night.
What’s happening Wednesday?
In broad strokes, Biden and Kamala Harris will be sworn in as president and vice president shortly after noon ET, and Biden will deliver his first presidential address to the country. At night, he is forgoing the traditional inaugural balls because of the pandemic, and he will instead take part in a television event called “Celebrating America.”

Who will — and won’t — be in attendance?
As was the case with previous inaugurations, most of Congress and the Supreme Court are expected to be in attendance, as are some former presidents. Barack Obama, George W. Bush and Bill Clinton are all set to attend, as are former first ladies Michelle Obama, Laura Bush and Hillary Clinton. Jimmy Carter, the country’s oldest living former president, at 96, and former first lady Rosalynn Carter will not be there, but they sent their “best wishes.” The inauguration is the first they have missed since Carter was sworn in in 1977.

Also absent will be Trump, making him the first president to skip his successor’s inauguration since Andrew Johnson in 1869. Vice President Mike Pence will attend.

What’s the schedule for the swearing-in?
The exact start time hasn’t been announced, but the event is expected to begin around 11 a.m. ET at the West Front of the Capitol.

The proceedings will begin with an invocation by the Rev. Leo J. O’Donovan, a Jesuit priest who is the former president of Georgetown University and a close friend of the Biden family. Andrea Hall, the first African American female firefighter to become captain of the Fire Rescue Department in South Fulton, Georgia, will recite the Pledge of Allegiance.

Lady Gaga — who teamed with Biden on domestic violence issues when he was vice president and campaigned for him in the 2020 election — will sing the national anthem.

Amanda Gorman, who became the country’s first Youth Poet Laureate in 2017, will read a poem she has written for the occasion called “The Hill We Climb.” Like Biden, Gorman had a speech impediment that she has worked hard to overcome. She has also announced plans to run for president herself in 2036 — the first election she’ll be old enough to do so.

Gorman will be followed by a performance by Jennifer Lopez, like Gaga a former Super Bowl performer. Brooks, who played Obama’s inauguration in 2009, will also perform.

A longtime friend of the Biden family, the Rev. Silvester Beaman, pastor of Bethel African Methodist Episcopal Church in Wilmington, Delaware, will deliver a benediction.

Who is swearing in Biden?
As is tradition, the SCOTUS chief justice, John Roberts, will administer the oath of office to Biden just after the clock strikes 12. Biden will take the oath with his hand on top of his 127-year-old, 5-inch-thick family Bible, which will be held by his wife, Jill Biden.

Who’s swearing in Harris?
Harris, the first woman, the first Black American and the first South Asian American vice president, will be sworn in by Justice Sonia Sotomayor, the first Latina member of the Supreme Court. Like Harris, Sotomayor is a former prosecutor.

Sotomayor has experience swearing in vice presidents — she administered the oath to Biden as vice president in 2013.

What’s the theme of Biden’s address?
The inaugural theme is “America United,” a theme Biden campaigned on and which he is expected to focus on in his speech.

A transition official said Biden was still working on the speech over the weekend with family members and senior adviser Mike Donilon. In addition to unity, he is also expected to speak about healing and to lay out his vision for the many crises the country faces in a plain-spoken way.

What about Covid-19?
Many safety protocols will be in place because of the coronavirus, which will give the ceremony a different look from those of years past. Attendees will be socially distanced, and they will have to wear masks.

The precautions — and a desire to stop people from traveling during the pandemic — led the Joint Congressional Committee on Inaugural Ceremonies, which is in charge of putting the inaugural together, to drastically reduce the number of people who are invited. The committee typically makes 200,000 tickets available for members of Congress, but this year every lawmaker gets two. The committee said the number of attendees will be about the same as when the president delivers a State of the Union speech inside the Capitol, about 1,000 people.

What about security after the riot?
Numerous extra security precautions were put in place after pro-Trump supporters breached the Capitol during the electoral vote count. Over 25,000 National Guard members have been called up to keep the event secure, extra security fencing has been erected near the Capitol, and the White House and numerous streets have been shut down.

The National Mall, usually a place for onlookers to gather, has been closed down, a first. Two groups that had permits for demonstrations agreed to hold them in different areas nearby, and attendees will be screened on their way to the demonstrations.

While Biden has pushed back against suggestions to move the event indoors, the threat of violence has forced some changes. A rehearsal originally scheduled for Sunday was delayed until Monday, and then it was briefly interrupted when a small explosion at a nearby homeless encampment caused a security scare. Precautions also forced Biden to scrap his plans to take a ceremonial Amtrak trip to Washington from Wilmington.

What’s happening after the ceremony?
After the swearing-in ceremony is completed, Biden and Harris will take part in a Pass in Review with members of the military on the East Front of the Capitol. Pass in Reviews are a military tradition that honor the peaceful transfer of power to a new commander-in-chief, and every branch of the military will be represented.

After the review, Biden, Harris and their spouses will honor the military by going to Arlington National Cemetery in Virginia, where they will lay a wreath at the Tomb of the Unknown Soldier. The Obamas, the Bushes and the Clintons will attend the wreath laying ceremony, as well.

Inauguration Parade

After the wreath ceremony, the Bidens, Harris and Harris’ husband, Doug Emhoff, will head to the White House for the first time as president, first lady, vice president and second gentleman, the title Emhoff has chosen for his new role. They will get a presidential escort there, which will include representatives from every branch of the military, as well as the drumlines for the University of Delaware and Howard University — Biden’s and Harris’ alma maters.

That will kick off the virtual “Parade Across America” at 3:15 p.m., featuring performances from all 56 states and territories. The event, hosted by the actor Tony Goldwyn, will feature appearances by Earth, Wind and Fire and former “Daily Show” host Jon Stewart. The parade will also feature heroes from across the country, including Jason Zgonc, 12, an Atlanta trumpeter who played for hospital workers during their break times over the summer to cheer them up.

Celebrating America
The grand finale is a star-studded, made-for-TV event called “Celebrating America,” which will air at 8:30 p.m. ET.

The event is being hosted by Academy Award winner Tom Hanks, and Eva Longoria and Kerry Washington will introduce segments of the special, which will include “stories of young people making a difference in their communities.”

Scheduled performers include rock legend Bruce Springsteen, Foo Fighters, John Legend, Jon Bon Jovi, Justin Timberlake, Demi Lovato, Ant Clemons, Lin-Manuel Miranda, Tim McGraw and Tyler Hubbard. The inaugural committee said they will perform from “iconic locations across the country.” The 90-minute telecast will also feature remarks from Biden and Harris.

How to watch live

All major networks will carry the inauguration live. ABC, CBS, CNN, NBC News will begin special coverage at 10 a.m. ET, while MSNBC begins special coverage at 6 a.m. ET. NBC News Now will stream wall-to-wall coverage beginning at 7 a.m.

The Choice, a free streaming channel on Peacock, will host special coverage beginning at 8 a.m. NBCNews.com will have a live blog featuring news and analysis.

“Celebrating America” will be carried live by ABC, CBS, CNN, NBC and MSNBC and streamed live on the presidential inaugural committee’s social media channels on YouTube, Facebook, Twitter and Twitch.