The Umbrella Academy: Dallas (2008)

Gerard Way and Gabriel Bá's second six-issue series turns its time travel into a family argument. Number Five, it emerges, once worked for a shadowy timeline protection organisation that tasked him with killing John F. Kennedy, and a mistake from that job threatens another apocalypse, so the family heads back to the 1960s with half of them trying to eliminate JFK and the other half trying to save him. The sharp joke underneath is that the "correct" history is the one with the assassination in it, so protecting the timeline means doing something terrible. Fans of the television series will recognise plot points that resurfaced in its second season, but the comic is tighter and stranger.