The latest episode of Gotham season 5 potentially sets up how Barbara Gordon - better known to the city's criminals as Batgirl - could exist within the show's continuity. Essentially serving as a Batman prequel series, Gotham is centered around the early exploits of Jim Gordon, the man who eventually becomes the DC Universe's famous Commissioner. However, flicking on the Bat-signal when things get tough isn't Gordon's only contribution to Batman mythology - he's also the father of Barbara Gordon.

As with many comic characters, Barbara Gordon has several slightly different backstories and origins, but in more recent continuity her mother is revealed to be a woman called Barbara Kean. It seemed natural for Gotham fans to initially assume that the Barbara Kean played by Erin Richards would ultimately prove to be Batgirl's mother, especially since she and Jim Gordon were an item in season 1. However, this did not come to pass.

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The two were quickly embroiled in a particularly messy breakup and their split was made even nastier by Barbara's slow descent into mental instability and crime. As the hatred between the former lovers grew, two problems emerged. Firstly, Batgirl's parents were too busy shooting at each other to have a child, and secondly, even in the event that Jim had a baby with one of his many other love interests, why would he name the infant after his crazy ex? Because of this, it wasn't clear how Batgirl could possibly come into the Gotham story and many viewers were left to wonder whether the show was omitting Batgirl's future entry into the franchise completely.

Erin Richards as Barbara Kean and Ben McKenzine as Jim Gordon in Gotham

The issue has been ignored for much of Gotham's time on screen but, with the show confirmed to be coming to an end with season 5, there appears to be some resolution for fans of Batgirl in the season's fourth episode. Shortly before the final credits, "Ruin" finds Jim Gordon solemnly sipping a glass of whiskey after a hard day of gunfights, starvation and general catastrophe. He's soon joined by Barbara Kean, and is none too pleased to see her, given that the pair have been on frosty terms for 3 seasons or so. Surprisingly, Barbara begins to put the moves onto Jim and after some half-hearted resistance, the weary cop gives in and the two rekindle their romance.

Never a show that delves too far into explicit territory, Gotham leaves what happens next to the audience's imagination, but it's safe to assume that things went further than what was actually shown on screen and it's also likely that, as with everything in No Man's Land currently, contraception is in short supply.

Gotham could take several different routes with Jim and Barbara's revived relationship. Their dalliances may continue throughout the season, or perhaps Barbara will reveal to Jim that she has fallen pregnant in an upcoming episode. However, even if this moment of passion fails to turn into a fully-fledged storyline and is never mentioned again, Gotham has still provided an implied origin story for Batgirl using the same parentage she had in the comic books.

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Erin Richards as Barbara Kean and Ben McKenzie as Jim Gordon in Gotham

There are several other factors at play here that add weight to the argument that this episode sees the (literal) conception of Batgirl. Firstly, since Gotham is coming to end in less than 10 episodes, it's not necessary to show Barbara during or after her pregnancy. The consequences of this scene don't have to be dealt with and a main character doesn't need to be temporarily written off to give birth. Everything can take place in the period after Gotham's conclusion.

Secondly, the timing of this potential conception would make Batgirl's relative age to Bruce Wayne more or less accurate to the source material. David Mazouz's junior Batman is currently in his late teens or thereabouts and after another 9 months, Bruce would be roughly 20 years old at the time Barbara Gordon is born. Given that Gotham season 1 already introduced a pregnant Mary Grayson, this would make the relative ages of Batman, Robin and Batgirl line up approximately to canon.

Gotham has placed much focus on Bruce Wayne's gradual development towards becoming Batman and with fans invested in the birth of one classic superhero, it was easy to forget that Jim Gordon's destiny to play a significant role in creating another. It's almost certain that Batgirl won't actually appear in Gotham, even if the rumors of a major final episode time jump prove correct, but given how important the Barbara Gordon character is to Gotham's lead protagonist, it would've been disappointing if the show had ended without at least setting up her birth.

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Gotham season 5 continues with 'Pena Dura' January 31st on Fox.