HMCS Chicoutimi is a Victoria-class long-range hunter-killer (SSK) submarine of the Royal Canadian Navy, originally built and operated by the Royal Navy as HMS Upholder.

171018-N-XN177-140 YOKOSUKA, Japan (Oct. 18, 2017) The Valiant-class yard tugboat Seminole (YT 805) assists the Royal Canadian Victoria-class long-range hunter-killer submarine HMCS Chicoutimi (SSK 879) as the submarine arrives at Fleet Activities (FLEACT) Yokosuka for a port visit. FLEACT Yokosuka provides, maintains and operates base facilities and services in support of the U.S. 7th Fleet's forward-deployed naval forces, 71 tenant commands and 24,000 military and civilian personnel. (U.S. Navy photo by Mass Communication Specialist 1st Class Peter Burghart/Released)

Shortly after being handed over by the United Kingdom to Canada she was involved in a partial flooding incident which resulted in a fire at sea. The incident sparked a fierce debate over the value of the purchase of this group of second-hand vessels, as well as the handover inspection process. The subsequent investigation "determined the fire was caused by human, technical and operational factors, [and] the board cleared the commanding officer and crew of any blame."[1] The submarine was repaired and entered Canadian service in 2015.

https://en.wikipedia.org/wiki/HMCS_Chicoutimi_(SSK_879)