'This Is Us' episode 12 spoilers: show offers a new perspective on the day the Pearson kids were born

Tonight's installment of "This Is Us" throws a curve ball once again to its viewers with an episode devoid of the present as the show solely tackles events from the past.

That only means that fans should not expect Sterling K. Brown's Randall, Chrissy Metz's Kate, and Justin Hartley's Kevin popping on the small screen when the show starts as the story will go back to the day the three kids were born. Obviously, the narrative has already been told before as it is basically where "This Is Us" started. But this time, that fateful day gets a new perspective showing what other game players were doing that day that may have contributed to Jack (Milo Ventimiglia) and Rebecca (Mandy Moore) bringing three babies home.

The official synopsis for the episode titled "The Big Day" reveals that there will be three separate stories eventually coming together in the narrative. The Pearsons who are anxiously waiting for the birth of their triplets led to Rebecca eventually forgetting Jack's birthday. It can be remembered that during the pilot episode of the show, the outing opens up with the two carrying a birthday tradition, which apparently almost did not happen.

Meanwhile, Dr. K. (Gerald McRaney) who eventually delivered Kevin, Kate and the last baby who did not make it was actually struggling a bit harder on the very same day about the passing of his wife. Again, rounding back to the series premiere, he talked a little bit about it with Jack as something that he carries prompting him to continue working despite his age.

Finally, fans will also have the chance to see what Randall was talking about when he tried to tell how he was found after William (Ron Cephas Jones) abandoned him on the steps of a fire station. As it turned out, the firefighter, Joe (Brian Oblak), who eventually found the swaddled baby, was also going through some tough times as he dealt with marital issues with her wife. Series creator Dan Fogelman tells Entertainment Weekly that viewers will be treated to a bit of a backstory of the man that brought baby Randall to the hospital, only to be adopted by Jack and Rebecca later in the day.

"We see the fireman who found Randall in his fire station and follow him for the 24 hours leading to a doorbell ringing in his fire station and seeing a baby delivered there," he revealed.

How the specific situation will affect his marriage is yet to be seen. But given that the family drama has a knack for tying things together, it can be expected that there will be some domino effect there.

"This Is Us" airs every Tuesday, 9 p.m. ET on NBC.