Star Trek: The Next Generation – The Pegasus [7.12]

Riker’s former commanding officer arrives on board the Enterprise, using his rank as an admiral to usurp Picard’s authority on  a secret mission to recover their ship, the Pegasus, which has long been thought lost in an incident in which a young Riker protected his Captain from other mutinying officers.  This creates conflicted loyalties for Riker and strain in his relationship with Picard.