While Kenzi, Hale, and Dyson, are all living their lives, Bo is nowhere to be found.
It's later realized that they simply forgot Bo, as someone was forcing them to.
Tamsin discovers that by not taking the soul of a man named Rainer to Valhalla, she is part of the reason "The Wanderer" was created.
Bo is able to get back on the train, where she finally meets Rainer, and brings him back to the Dal.
The show title and credits are accompanied by the Lost Girl Theme song. I was lost for years, searching while hiding; only to find that I belong to a world hidden from humans. Total episode running time is minutes, including opening title sequence and closing credits roll.
Over the top of the sequence and theme song is the voice-over monologue by the protagonist, Bo (Anna Silk), summarizing her story: Life is hard when you don't know who you are. Episodes on Syfy in the United States are 90 seconds shorter to allow for more commercial advertisement time.
Most of the Fae considered Bo an unknown entity that should either be eliminated as a risk to their secret existence or exploited for their benefit.
Throughout the season, Bo learns more about the Fae world and herself while she searches for information about her origins.
Bo faces personal challenges with Dyson after she finds out The Norn took his ability to feel passion for her in exchange for giving her the strength to defeat Aife in the season one finale; and with Lauren when their relationship became complicated after The Morrigan informed Bo in "It's Better to Burn Out Than Fae Away" that Lauren had a girlfriend.
Hale and Kenzi admit their feelings for each other.
Lauren, who has been working with the Dark, somehow turns the Morrigan human.
Massimo has been giving Kenzi temporary powers to appear Fae.
Bo finally awakens to find herself on a train, and later jumps off.