The novel “All Clear” by Connie Willis was published for the first time in 2010. Along with “Blackout”, which is the first part of what is actually a two-part novel, it won the Hugo, Nebula, and Locus Awards as the best novel of the year.

Michael Davies, Merope Ward, and Polly Churchill are in 1940 for what was supposed to be a research on various events of World War II but something has gone wrong and the portals that were supposed to take them back to 2060 are not opening.

The three historians start thinking that what was considered impossible has happened: they have somehow altered history and as a result are trapped in 1940. In their situation, it becomes increasingly difficult to avoid getting caught up in the events of the war and make things worse.