This year's Six Nations is set to be awash with new faces and personalities.

Stalwarts Johnny Sexton, Alun Wyn-Jones, Stuart Hogg and Dan Biggar have all retired from Test rugby, while Owen Farrell and Antoine Dupont have ruled themselves out of selection.

The first tournament after a World Cup is usually a time for change as the northern hemisphere sides embark on the start of another four-year cycle.

So who will fill the void in 2024? BBC Sport profiles four young players looking to announce themselves in the Six Nations.

Nolann le Garrec

Nolann le Garrec is among two France scrum-halves facing the unenviable task of replacing Dupont, the 2021 World Player of the Year, who is widely recognised as the best number nine in world rugby.

Dupont is taking a break from the XVs game to focus on Sevens and competing for the hosts in the upcoming Paris Olympics.

Le Garrec was called up in the 2023 Six Nations squad but remains uncapped despite his promising form for Racing 92.

Maxime Lucu played back-up to Dupont in the World Cup and is likely to start against Ireland on the opening weekend, but Le Garrec could prove valuable with his sniping runs, impressive distribution and smart kicking game.

Immanuel Feyi-Waboso

Fly-half Farrell will be a notable absentee in England's backline, but could their attacking threat be provided elsewhere?

Wing Immanuel Feyi-Waboso possesses frightening speed, power through the tackle and an eye for the tryline with five in 10 Premiership matches for Exeter this season.

The Cardiff-born 21-year-old represented Wales at age-grade level but opted to make himself available to England, who he qualifies for through family heritage.

He could fill the vacancy on the wing after Jonny May retired from international rugby after the World Cup.

Jack Crowley

The Johnny Sexton era is over.

The end of the Ireland colossus' 14-year international career opens the door for someone else to claim his number 10 jersey and create their own legacy.

Munster fly-half Jack Crowley lifted the United Rugby Championship trophy last season and is likely to win his 10th cap against France, but will he be able to replicate the same temperament and game-management skills needed to steer the Ireland attack at the highest level?

Friday night's opening match in Marseille should gives us a good indication.

Sam Costelow

Like Ireland, Wales are also looking for a new mainstay at 10 after Dan Bigger called time on his 15-year Test career in October.

Scarlets fly-half Sam Costelow made his Wales debut in last summer's World Cup warm-up against England and is widely tipped to seize the opportunity, despite an injury-hit campaign.

The 23-year-old only returned to club action on New Year's Day after damaging both his shoulder and hamstring in Wales' win over the Barbarians in November.

But Biggar himself has said Costelow has the "X Factor" with his sound kicking game, distribution to keep defences honest and acceleration to exploit their weaknesses.

New captains

Retirements and unavailability are often catalysts for change in leadership.

Peter O'Mahony, 34, is no stranger to Test rugby and he will lead Ireland's defence of the Grand Slam in Sexton's absence. The experienced flanker has won 101 caps and previously captained Ireland on 10 occasions since making his debut in 2010.

Jamie George will stand in for Saracens clubmate Farrell as England skipper.The 33-year-old hooker has been capped 85 times but never captained either club or country. He is likely to start every game as the only senior hooker in the squad and is well-respected by his team-mates.

Fly-half Finn Russell is known for his talismanic attacking skills and reliable boot, but he will co-captain Scotland alongside flanker Rory Darge. The pair succeed Jamie Ritchie, who head coach Gregor Townsend said had done an "excellent" job but could now focus on his role on the flank. Russell, 31, has won 75 caps while 23-year-old Darge has played 15 Tests.

Wales lock Dafydd Jenkins is the youngest skipper in this year's Six Nations, aged just 21. It also makes him his country's second youngest captain after Gareth Edwards led Wales as a 20-year-old in 1968. Jenkins has played just 12 Tests but has shown exemplary leadership skills as Exeter Chiefs captain.

France, meanwhile, have turned to the experience of number eight Gregory Alldritt after Dupont's withdrawal. The 26-year-old has tasted success as captain before, leading La Rochelle to consecutive Investec Champions Cup titles. He has won 45 international caps and was preferred to former captain and Dupont's predecessor Charles Ollivon.

New coaches?

Italy's Michele Lamaro is the only captain to retain his role from the 2023 Six Nations but the Azzurri are under new management.

Former Argentina fly-half Gonzalo Quesada has taken the reins as head coach from Kieran Crowley and is tasked with avoiding the Wooden Spoon they finished with last year.

Quesada has previously coached Stade Francais and Biarritz after a role as France assistant coach.

Italy have lost all 24 home games in the Six Nations since beating Ireland in 2013, and they will begin their campaign against England in Rome.