The Tok'ra: Part 1

Plot:

When Teal'c makes Sam Carter realize how valuable the knowledge left by Tok'ra Jolinar in her brain and the chance for an alliance can be, they convince General Hammond to let SG-1 attempt a meeting. They arrive on a planet which is deserted on the surface, but are awaited by well-camouflaged, armed Tok'ra who bring them to tunnels which they create by means of a mysterious crystal, which can also undo them afterward. Both parties are quite suspicious, the team feels like captives, and indeed, the Tok'ra leader Yosuuf fears they cannot be released, at least until the whole site is moved. Meanwhile, the Tau'ri barely overcome their suspicion against the Tok'ra Goa'uld biology (with symbiote), when asked to volunteer themselves as 'hosts', and Carter learns Martouf (and his symbiote, Lantash) was Jolinar's lover, hence has a special connection with her.