Cardiff recall Wales half-backs Jarrod Evans and Tomos Williams to their starting line-up to face Harlequins in Europe's top flight on Friday.
Wales and British and Irish Lions wing Josh Adams is back on the wing with Wales flankers Shane Lewis-Hughes and Ellis Jenkins also returning.
Harlequins make three starting changes, two of them up front.
Dino Lamb comes in at lock with James Chisholm at blind-side flanker and Louis Lynagh on the wing.
Lamb's return means Hugh Tizard dropping to the bench, with Chisholm back following an injury to Jack Kenningham last weekend.
Cardiff's changes include six internationals returning with full-back Hallam Amos back to start alongside fly-half Evans, scrum-half Williams, Adams, Lewis-Hughes and Jenkins.
Hooker Kirby Myhill, 29, could be replaced during the game by 26-year-old brother Torin, who Cardiff have brought in from Welsh Premiership side Carmarthen Quins, because Liam Belcher, Iestyn Harris, Efan Daniel and Kristian Dacey are injured.
In December Harlequins overcame a team of Cardiff "misfits" after the Welsh team were caught up in Covid issues during an aborted United Rugby Championship trip to South Africa.
Dai Young's hosts hope they can now show what a full-strength team is capable of against the reigning English champions.
Cardiff: Amos; Lane, Lee-Lo, Halaholo, Adams; J Evans, T Williams; Carre, K Myhill, Arhip, Turnbull (capt), S Davies, Lewis-Hughes, Jenkins, Ratti.
Replacements: T Myhill, Domachowski, Lewis, Thornton, Boyde, L Williams, Priestland, B Thomas.
Harlequins: Green; Lynagh, Marchant, Northmore, Murley, Smith, Care; Marler, Walker, Collier, Symons, Lamb, Chisholm, Lawday, Dombrandt (capt).
Replacements: Riley, Botta, Kerrod, Tizard, Taulani, Stafford, Edwards, Jones.
Cardiff director of rugby Dai Young: "We can be really proud of the way the group came together to perform admirably in the opening two rounds in Europe back in December.
"The senior guys did a great job to lead the more inexperienced players during that period and they've taken confidence from that. I'd like to think it brought us a bit closer together. It was a difficult period but we stuck together and hopefully we've come out as a closer unit.
"For all the positives however, they were two defeats and we want to win every game we are involved in. We are determined to go one better this time around but know the quality that we face."
Harlequins scrum coach and former Cardiff, Wales and Lions prop Adam Jones: "When Cardiff came to our ground last time out they showed, despite having such a disrupted squad, they could fight fire with fire. There were a lot of boys that weren't even in the Cardiff squad and showed themselves worthy of regional selection.
"There's a lot of internationals in their team and they can certainly help raise the bar in these big games. That's going to be a challenge for us this week and we're going to have to stem the flow of passion and aggression that will come our way.
"It's the old Wales-England game, isn't it? Two capital city centre teams. We're expecting a tough game down there. We know they'll want to have a crack at the English champions and it'll be up to us to match it, and we will."
Match facts
Match officials
Referee: Tual Trainini (France)
Assistant referees: Benoit Rousselet & Cedric Marchat (France)
TMO: Eric Gauzins (France)