Angel (1999) - 5x13 - Why We Fight

Lawson, a mysterious man from Angel's past, arrives at Wolfram & Hart and takes the gang hostage. Through flashbacks to World War II, it is revealed that Angel worked with the U.S. Navy to recover a captured German submarine with American sailors on board. The ship also has a secret cargo, a dangerous trio of vampires, including Spike, who were kidnapped by the Germans and forced to help the Nazis. When the sub comes under attack, Angel saves Lawson's life by turning him into a vampire. Now, sixty years later, Lawson has arrived at Wolfram & Hart seeking revenge.