Allison Nichols, a 28-year-old pharmaceutical sales representative from Boston, MA, became the first individual houseguest evicted from Big Brother: 'Til Death Do You Part after last night's live broadcast of the CBS reality show's fourth eviction revealed an end to the season's previous couples pairings.

Allison and her "perfect-match" partner Ryan Quicksall, a 27-year-old college student from Columbus, OH, were initially revealed to be evicted from the Big Brother house by a 2-0 vote after they were placed on the chopping block by Head of Household couple Sharon Obermueller, a 23-year-old realtor from Olathe, KS, and Joshuah Welch, a 25-year-old advertising media buyer from Dallas, TX.

However as Allison and Ryan tried to exit the house, they found the door was locked -- and a horn the houseguests had previously been warned about began sounding, a signal for everyone to reconvene in the living room.

"This could be our saving grace," said Ryan, who along with Allison was visibly ecstatic.

"Houseguests, now that the horn has sounded, I have an important announcement for you," said host Julie Chen.  "I have news for you -- the game is about to change.  When you entered the house, you learned this was Big Brother: 'Til Death Do You Part.  Well, 'Til Death Do You Part is about to take on a whole new meaning.  From this moment on, you are no longer couples.  You are all playing as individuals for yourselves."

Julie then explained either Allison or Ryan -- not both -- would be leaving during the live eviction.  The eviction would be based on live votes cast by six other houseguests not including Joshuah and Sharon, who as outgoing HoH would only vote if there was a tie.

After the six houseguests -- James Zinkand, Chelsia Hart, Natalie Cunial, Matt McDonald, Adam Jasinski and Sheila Kennedy -- were given a few minutes to ponder their decision, each entered the Diary Room to cast their eviction votes. 

Allison was booted by a unanimous 6-0 margin.

"It doesn't feel good at all," Allison told Julie about exiting the Big Brother house sans Ryan.

Julie then asked the obvious question:  Why did Allison and Sheila start the false rumor about themselves that they were a pre-existing lesbian couple?

"It was just a joke really that got turned into something.  It was a knee-jerk reaction just to get a reaction from the house," said Allison.  "It really got blown out of proportion.  It wasn't meant to really stir anything up."

But stir stuff up it did -- most notably offending Joshuah, who accused Allison of concocting the story as a strategy that attempted to play to his sexuality as a gay male.

"Unfortunately it escalated and went further than it was supposed to," said Allison.  "It was just a mistake.  Unfortunately you can't turn back time and that was the situation."

Following Allison's eviction, the nine remaining houseguests -- minus Joshuah and Sharon, who as the outgoing co-HoH's, were still deemed ineligible to compete -- competed in the ninth season's first individual Head of Household competition.

Dubbed "Time After Time," the competition required the seven participating houseguests to answer a series of true or false questions about the order in which events have occurred in the house. One incorrect answer would eliminate a houseguest from the competition, and the last houseguest remaining would become HoH.

Despite thinking he had been evicted only a half-hour earlier, Ryan managed to answer the most questions correctly and became the season's first individual HoH.

After Ryan's victory, Julie informed the show's viewers -- but not the houseguests -- that another twist was coming to the Big Brother house. 

"America, it's time for you to get involved in the Big Brother game," Julie announced.  "Evicted houseguests Jacob, Jen, Parker, Amanda, and Alex have not returned to their regular lives [since leaving the Big Brother game], instead they've all been isolated from the outside world and have no idea what's been happening inside the Big Brother house. With your help, one of them -- including newly-evicted houseguest Allison -- will get the chance to shake things up by returning to the game!"

Similar to the show's 2006 twist that allowed home viewers to vote one of Big Brother 6's first four evicted houseguests back into the game (like this season's evictees, all four had been sequestered since their evictions), viewers will be able to visit and vote for whichever previously evicted ninth-season houseguest they wish to see re-enter the game.  The houseguest that receives most votes will then re-enter the Big Brother house during next Wednesday's Big Brother: 'Til Death Do You Part broadcast.

Big Brother: 'Til Death Do You Part's next episode will air Sunday, March 9 at 8PM ET/PT.
About The Author: Christopher Rocchio
Christopher Rocchio is an entertainment reporter for Reality TV World and has covered the reality TV genre for several years.