The episode opens with Daniel Jackson confined to the infirmary recovering from an appendectomy. The rest of team is told to take a vacation. O'Neill wants to go fishing and Carter wants to stay on base to work on a project. As O'Neill is leaving he is suddenly transported to Thor's ship where he encounters many mechanical spiders. When he finds Thor he is informed these are replicators, an even greater enemy to the Asgard than the Goa'uld. He tells O'Neill that they need his help to defeat them.