By night, in the late nineties, The Bandbox club and Splitz bar had countless coatless young people lining up outside the doors to get inside. Often, the wait was cold in the biting North Sea air; partygoers shuffled slowly in the queue as bouncers decided who could get in, but this didn’t deter people from hanging around. By day, Felixstowe in Suffolk is more slow-paced — tourists and retirees enjoy fish & chips, ice cream and blue flag beaches. Life is peaceful. Be that as it may, a senseless murder in 1999 was one of the biggest and most complex cases officers in the port town ever had to investigate…