Where can I watch “Lost” Season 6 Episode 15 online?

This page provides episode info and a legal-only guide. It does not host streams or downloads. Check official platforms and licensed services for availability in your region (US first).

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Watching earlier episodes in season 6 helps you follow the plot and character arcs leading into this episode.

Watch Lost Season 6 Episode 15 Online

“Across the Sea” — Watch "Lost" Season 6 Episode 15 online in HD for free. Check streaming providers, cast, and episode details.

May 11, 2010 Season 6 Episode 15 44 min 15

8.1 ★ ★ ★ ★ ★

51 votes

Lost Season 6

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Where can I watch "Across the Sea" online?

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Season 6 Episode 15 — Aired on May 11, 2010 • runs about 44 minutes.

Directed by Tucker Gates.

Written by Carlton Cuse, Damon Lindelof.

Notable cast/guest names in this episode include Matthew Fox, Evangeline Lilly, Terry O'Quinn, Josh Holloway.

This page includes 2 official still(s) (when available) plus legal availability links.

Looking for “watch Lost Season 6 Episode 15 online”? This is a legal-only guide with synopsis, stills, and navigation for this season.

Synopsis

Jacob and the Man in Black are revealed to be twin brothers. They are raised by a mysterious woman who is charged with protecting the island. As revenge for the murder of their adoptive mother (who killed their real mother), Jacob throws his brother into the source of electromagnetism after being made the island's guardian, which transforms the Man in Black into the smoke monster.