Star Trek: 10 Best Odo Episodes

Set during the time when the Founders had taken away Odo's ability to shapeshift, Quark comes into possession of an infant changeling. This is presumably one of 'The Hundred' that were sent out as scouts into the stars, as Odo himself was. Our constable attempts to make contact with the Infant Changeling but becomes wary when Dr. Mora Pol appears to help him, having arrived from Bajor.

While Odo and Mora had tried to settle some of their differences in The Alternate, there is still some lingering resentment towards his 'teacher'. This becomes apparent when their attempts to stimulate the Infant differ widely and the former Changeling reveals some of the ways that he used to tease or infuriate Mora, back in their days in a Cardassian laboratory.

With the secondary story in this episode being about Kira giving birth (as a surrogate mother) for the O'Briens, there's a sense of parental loss that runs through this episode. The Infant Changeling does not survive and instead merges with Odo, restoring his ability to shapeshift at the cost of its own, brief life.