said goodbye to forensic scientist Abby Sciuto (played by Pauley Perrette) back in season 15, when she decided it was finally time to hang up her lab coat following the death of Agent Clayton Reeves (Duane Henry). Unlike many of the characters in the drama, Abby didn't have much of a love life in the show. However, it could have been a very different story if things worked out between herself and one of the team's key agents.
While Abby was in NCIS from the very beginning, Agent Timothy McGee (Sean Murray) wasn't introduced until season one episode seven, Sub Rosa.
They initially started speaking over the phone and to try and impress her, McGee even got a "Mom" tattoo on his backside.
This came across as a sweet gesture to Abby and they went out on a lunch date together.
Throughout the first series, it seemed like McAbby were going to be the show's starring couple.
This difference in attitude towards their love life ultimately led to their downfall.
In season two, fans saw less of the spark between Abby and McGee with their romance gradually transforming into more of a brother-sister relationship.
While the show hasn't confirmed why it chose to end McAbby, there is a theory it was to make room for Tony Dinozzo (Michael Weatherly) and Ziva David's (Cote de Pablo) romance to blossom.
Matt Roush at TV Guide previously suggested "pairing up all four members of Gibbs' team romantically might seem like overkill, and the Tony-Ziva dynamic... is so integral to the show's core".
Referencing their previous relationship, Perrette told TV Guide in 2010: "There will always be something between McGee and Abby.
"They may not be a couple, but they do love and respect each other."
While Abby has remained single for the majority of NCIS, McGee started dating Delilah Fielding (Margo Harshman) from the Department for Defence at the end of season 10.
They got married in season 14's Something Blue and now have twins together.
However, things haven't been going too well between the couple as of late.