The teams who started the 33rd season of “The Amazing Race” in February 2020 were shocked when they were told in Scotland that their race was being suspended due to the coronavirus, but likely felt they would get to come back within a few months to resume their competition. Unfortunately, after the pandemic continued to wear on, making it unsafe for teams to return for 19 months total, some were unable to come back.

In a brief preview for Episode 4, which was filmed in Fall 2021, five of the remaining nine teams in the competition were pictured meeting up with host Phil Keoghan again, this time, in Switzerland. Those teams, seen in a preview clip, were married Internet personalities Kim and Penn Holderness, best friends Ryan Harris and Dusty Ferguson, flight attendants Raquel Moore and Cayla Pratt, twin radio hosts Mariana “Lulu” and Marissa “Lala” Gonzalez and married educators Akbar and Sheri Cook. Missing were friends and heroes Anthony Sadler and Spencer Stone, married couple Connie and Sam Grenier, dating couple Caro Viehweg and Ray Gantt and married Youtubers Taylor and Isaiah Green-Jones.

Co-Creator and Executive Producer Elise Doganieri had previously confirmed that only seven teams were able to return after the long hiatus, which, following the preview clip, seems to indicate that with the four teams who were missing, to cover the gap, they brought back previously eliminated pairs, singing police officers Michael Norwood and “Moe” Badger and father/daughter team Arun and Natalia Kumar.

No official reasons have been given as to why the four teams who didn’t return were unable to come back, but social media has yielded a few likely clues.

For Connie and Sam, a pregnancy forced them to take themselves out of the race, as she posted on Instagram in December that they had welcomed a newborn son. Because she was pregnant when the race resumed in the Fall, she and Sam were unable to return.

Similarly, it’s likely that Caro and Ray did not return because while they were still a newly-dating long-distance couple when they started the race, they broke up by July of 2020, something Caro confirmed in a Youtube video. Because the pair were no longer together and had actually been broken up for more than a year at that point, they also did not return when filming resumed.

It is unclear why Taylor and Isaiah did not return, nor is there an official reason that has been given for Anthony and Spencer. It’s unclear if the pair’s reasons will be disclosed after the official unveiling on Episode 4.

“The Amazing Race” airs Wednesdays at 9 p.m. EST on CBS.

Amazing Race 33
The cast of "The Amazing Race" Season 33 is pictured. Sonja Flemming/CBS