From her perfectly styled hair to her elegant floral dress, the Suits star gave off major Kate Middleton vibes, while Prince Harry looked dapper in a white dress shirt and slacks. At one point, Markle sweetly put her hand around her beau's back while the two were sitting at a table, drinking champagne with another guest.
The lovebirds reportedly arrived in Montego Bay on Thursday -- Markle arrived via private jet, while Prince Harry reportedly paid approximately $3,000 for a commercial flight slightly better than coach.
"This is a big event for Prince Harry, because it's one of his best friends getting married," ET royal correspondent Katie Nicholl explained before the two touched down in the Caribbean. "It's a big deal for her to be going as his plus one. This wedding will be a huge amount of fun. There will be a lot of alcohol going down."
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Prince Harry and Meghan Markle
Prince Harry and Meghan Markle
File photos of Meghan Markle and Prince Harry, as Harry's girlfriend has been subject to a "wave of abuse and harassment" by the media, Kensington Palace has said in a statement.
NEW YORK, NY - JULY 14: Actress Meghan Markle enters the 'Today Show' taping at NBC Rockefeller Center Studios on July 14, 2016 in New York City. (Photo by Ray Tamarra/GC Images)
Prince Harry arrive at the London Eye on World Mental Health Day on October 10, 2016 in London, England.
(Danny Martindale/GC Images)
TORONTO, ON - JUNE 09: Actress Meghan Markle attends Luminato Big Bang Bash 2016 held at the Hearn Generating Station on June 9, 2016 in Toronto, Canada. (Photo by George Pimentel/WireImage)
NOTTINGHAM, ENGLAND - OCTOBER 26: Prince Harry plays rugby with children as part of the Coach Core sporting apprenticeships at National Ice Centre on November 6, 2016 in Nottingham, England. (Photo by Samir Hussein/WireImage)
Meghan Markle attends the Elton John AIDS Foundation's 13th Annual An Enduring Vision Benefit in New York October 28, 2014.
LONDON, ENGLAND - OCTOBER 07: Prince Harry takes part in sports activities during a visit to celebrate the expansion of Coach Core at Lord's Cricket Ground on October 7, 2016 in London, England. (Photo by Mark Cuthbert/UK Press via Getty Images)
NEW YORK, NY - APRIL 27: Actress Meghan Markle attends Glamour and L'Oreal Paris Celebrate 2016 College Women Of The Year at NoMad Hotel Rooftop on April 27, 2016 in New York City. (Photo by Nicholas Hunt/Getty Images for Glamour)
Britain's Prince Harry arrives at Lord's cricket ground in London on October 7, 2016, to participate in a Coach Core sports coaching apprenticeship programme event. Prince Harry, Patron, attended an event at Lord's Cricket Club to mark the expansion of the Coach Core sports coaching apprenticeship programme. The Prince met with apprentices, coaches and some of the partners and supporters who are taking the successful programme to 100 partners across the UK by Spring 2017. / AFP / JUSTIN TALLIS (Photo credit should read JUSTIN TALLIS/AFP/Getty Images)
TORONTO, ON - MAY 31: Actress Meghan Markle attends the Instagram Dinner held at the MARS Discovery District on May 31, 2016 in Toronto, Canada. (Photo by George Pimentel/WireImage)
Britain's Prince Harry attends the Metropolitan Police Service Annual Ceremony of Remembrance for colleagues who lost their lives in the line of duty, at the Metropolitan Police Training College in London, Britain October 20, 2016.
NEW YORK, NY - JULY 14: Actress Meghan Markle leaves the 'Today Show' taping at NBC Rockefeller Center Studios on July 14, 2016 in New York City. (Photo by Ray Tamarra/GC Images)
Actress Meghan Markle arrives on the red carpet for the MuchMusic Video Awards (MMVAs) in Toronto, June 16, 2013.
Prince Harry takes part in a training session during a celebration for the expansion of Coach Core at Lord's Cricket Ground on October 7, 2016 in London, England.
(Ben A. Pruchnie/Getty Images)
TORONTO, ON - APRIL 28: Actress Meghan Markle attends the Roland Mouret private dinner at Corkin Gallery on April 28, 2016 in Toronto, Canada. (Photo by GP Images/WireImage)
Actress Meghan Markle attends the USA Network and The Moth's Characters Unite Event at the Pacific Design Center in West Hollywood, California February 15, 2012.
Britain's Prince Harry arrives for the Sentebale Royal Salute Polo Cup in Wellington, Florida, U.S., May 4, 2016.