Calderwood, 28, is one of the 16 women included in the cast of the UFC's reality TV show which will this season end in the crowning of the organisation's first ever straw-weight (115lb) women's champion.
The undefeated fighter from Kilmarnock follows in the footsteps of her Dinky Ninja Fight Team stablemate Rab Whiteford, who made his UFC debut last year and won his most recent outing in the world's biggest MMA promotion.
Even if Calderwood doesn't win the show's grand finale, it is thought she has already secured a contract to fight for the organisation in the short to medium term at least.
The Ultimate Fighter (TUF) 20th season - officially dubbed A Champion Will Be Crowned - marks the first time it has featured an all-female cast. The women will be split into two teams and coached by UFC lightweight champion Anthony Pettis and contender Gilbert Melendez, who will themselves fight at the conclusion of the season.
TUF 20 kicks off later this year on BT Sport with a two-hour season premier.
Calderwood - who boasts an 8-0 perfect record - has won fans far and wide for her clinical striking and her softly-spoken persona outside of the cage.
She will be up against a cast of talented female athletes including a former International Kickboxing Federation women's bantamweight, a United States kickboxing champion and a former professional ice hockey player.
One of the other competitors, Australian Bec Rawlings, has tried to talk up a rivalry with Calderwood via social media, but the laid back Scot previously told Herald Sport she wouldn't bite.
The pair were rivals on all-female promotion Invicta, but never fought. The UFC will be hoping the ready-made 'beef' leads to fireworks in the house.