Watch: Inside Titanic sub before it went missing
In 2022, the BBC filmed inside the OceanGate Titanic submersible that has gone missing during a dive to see the wreck.
US and Canadian search teams are racing against time to find the vessel, which lost contact about an hour and 45 minutes into a dive on Sunday.
It's believed Stockton Rush, the chief executive of OceanGate who features in this video, is one of five people on the vessel.
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