In the finale of the show, Coop's 'test' at the hands of the evil spirit Bob, as he tries to rescue Annie, after entering the Glastonbury Grove and finding the Black Lodge runs something like this:
- He first meets the Dancing Midget, The Giant and finally Laura Palmer in one of the 'waiting rooms'.
- The giant/waiter appears, and offers him coffee, then sits next to the Dwarf, saying "One and the Same". Then he vanishes.
- Coop reaches for the coffee, but Bob has made it solid, so he cannot
drink.
- The midget notices this, and praises Bob: "Wow Bob wow. Fire walk with me." This freaks Coop out a bit.
- Coop, finally gets up and leaves the waiting room, discouraged but determined after losing the 'first round'. He walks down a velvet draped corridor into another waiting room.
- Coop next meets Maddie, Laura's dead 'twin' cousin, who warns him to look out for Laura. He ventures into yet another room, looking similar to the room he just left but now emptied of furniture.
- The midget doppelganger appears (his eyes are milky and blind looking) and warns Coop about, well, Doppelgangers.
- In yet another room, under a flicking strobe, Laura's dopplegänger writhing and shrieking scares Coop, and he backs off after being injured, trailing blood from his old stomach wound, but he returns to the room to face Laura again. This seems to heal him as he enters another room.
- Coop next faces Wyndom Earle, who confuses Coop about his love for the dead Catherine
versus his love for Annie, as both appear, claiming to be the other. Coop defeats Earle though, freely offering his own life for Annie's safety. Earle seems to try to stab Coop but is held suddenly still by Bob. Wyndom Earle has apparently broken a rule of the Lodge, in asking for a soul (maybe because he is not a spirit himself?) and is destroyed by a vengeful Bob, who then tells Coop he can go.
- Coop leaves to exit the Lodge back the way he came, but, at the last moment, runs from his doppelgänger who has appeared to chase him out and catches up to him just as he reaches the exit into the glade.
The dopplegänger, the evil side of the self which Hawk warned Cooper about, manifests the worst fear about one's self. Cooper's worst fear, indeed seemingly his only fear, is failing the people who've relied on him. In other words, he's not always capable of stopping evil things from happening. Major Briggs underscored this theme of Lynch earlier, when asked his greatest fear, replying: "The possibility that love is not enough". Lynch even had the same actor thinking in the earlier movie Dune that "fear is the mind killer".
The reminder of Cooper`s fallibility, which the doppelganger conjures up (even after he's defeated Earle and rescued Annie) spooks him into succumbing to fear; that insecurity is all that Bob needs though, and so Cooper is trapped inside the Black Lodge, and his dopplegänger is let lose on the world. From the final episode and the 1992 film Twin Peaks: Fire Walk With Me it is implied that Dale's spirit remains trapped within the Lodge, in a sort of limbo neither dead nor alive, while his possessed body is freed into the world along with Annie Blackburn.