They are set in 1761, aboard The Black Pearl, and the serial overall is titled The Strangest Places. Chronologically, these encompass the very beginning of the Echoes the Sea series.
The Strangest Places ~ Jack Sparrow, Charlotte
Do No Harm ~ Methos, Charlotte
Hand of Fate ~ Methos + Jack sparrow
Unexpected ~ Jack Sparrow, Charlotte, with a hint of Jack/Charlotte
Over the Horizon ~ Methos, Charlotte