24. Time's Orphan

Miles and Keiko O'Brien take their children to the planet Golana for a picnic. While playing, eight-year-old Molly falls into an abandoned time portal, which closes after Molly passes through. It sends her 300 years into the past to a time when the planet was uninhabited. The crew of Deep Space Nine helps the O'Briens recover Molly by reopening the portal and using a transporter to lock onto her signal. However, they find the portal has opened at a different time. The Molly they rescue is 18 years old and has grown feral, having survived alone for ten years. She is brought back to the station and placed in a special habitat made to resemble Golana.

Molly slowly remembers her parents, but is still barely controllable. She asks her parents to take her home, but later makes it clear that she wants to be returned to Golana. Her parents take her to a holosuite simulation of Golana. She responds positively, but when the simulation is deactivated, she becomes violent and assaults a man. Starfleet informs the O'Briens that it plans to put Molly into a mental institution, which worries them. With help from a sympathetic Odo, they arrange to return Molly to Golana, planning to destroy the portal afterwards to prevent Starfleet from finding her.

Molly returns through the portal but encounters her younger self shortly after she had fallen through. The older Molly points her younger self back through the portal, then as soon as the younger Molly returns, the older Molly disappears. Molly reappears moments before Miles is about to destroy the portal, and the family reunites happily.