“Phoenix Rising” is episode one of season two of Eureka.
At the end of the season one finale, “Once in a Lifetime”, Carter had gone back four years into the past to stop Henry from stopping the accident with the mysterious artefact (now said to be a fragment of a previous universe, which is rather impressive) which killed Kim, as his actions had started making the universe unravel as two different time lines collided.
As a consequence, both Jack and Henry have memories of an alternate four years. Carter thinks this will give them an advantage; Henry tells him that things will already start diverging.
Something starts changing immediately. Whilst watching a solar eclipse, one of the watchers suddenly combusts. Then someone else does.
People are catching fire and no-one knows why, and Stark is being censured for his actions in the accident that killed Kim.