Allow me to start off by explaining the episode title is not what one might think. Yes, the show has taken a wild turn since several of the main characters took a trip back to 1947 ("Founders Day"). They returned, but found things were not exactly the same as when they left. However, nobody requires a joint in order to cope.
Perhaps the biggest adjustment has been that of Dr. Trevor Grant (James Callis). He works with Albert Einstein to make Eureka into the the town of science gurus it is currently. He hitches a ride into current day 2010, and trouble manages to follow ("A New World"). To explain his presence, Fargo (Neil Grayston) decides Grant will become Charles Grant, science historian. Fargo is now head of Global Dynamics, the place where technology is developed for the Department of Defense. Few have a problem with the title, but Jack Carter (Colin Ferguson) is too busy being sheriff to quibble.
For the other romance part, the triangle played by Ferguson, Callis, and Salli Richardson Whitfield, who is cast as Dr. Allison Blake, is still playing out. Callis has three episodes left on his contract. Will he leave with Richardson Whitfield, or disappear like Nathan Stark ("I Do Over")? Time tells.
Ferguson wisely narrates a recap of the season through clips of past episodes before the episode starts. Wise move, since figuring out what goes in which timeline can be a little tricky. Relationships have changed, jobs are not in the same locations. Both past and present are colliding, and the end result could wind up in disaster.
Science has always played a part in this series, even if storylines are seriously fiction. This week stretches credibility with the fossil setup. I'm okay with the statue bit, but how it works out doesn't sound very likely. Of course, this is also television. Perhaps it shouldn't make sense as a rule.