It is almost a truism these days that the eerie "Hush" (Buffy 4.10), an episode with almost no dialogue, was Whedon's perverse reaction to praise for great dialogue, and the semi-pornographic (and less successful) "Where the Wild Things Are" (Buffy 4.18) his reaction to network censorship of the show's level of violence. With the move of Buffy to the UPN, and the insistence by the WB that there be no crossover episodes, it seemed that they would have to end; yet once again, Mutant Enemy has surprised us. In the current seasons of Buffy and Angel, we see Whedon's rebellion against network dictates, with closer ties than ever between the shows.

Perhaps the most apparent instance of this is the Angel episode "Carpe Noctem," in which the elderly Marcus, afraid of his own mortality, swaps bodies with the ensouled vampire Angel. While Angel struggles to escape the old-people's home in which he is essentially imprisoned in a failing body, the discovery that he has the body of a vampire sends Marcus on a killing spree across L.A. Here is a human who revels in the bloodlust and super-strength of his vampire nature.

FAKE ANGEL (to Angel-in-Marcus's-body): "Vampires don't help people, you moron, they kill them. Here, let me show you."

The overt message of this episode can then be contrasted with Buffy's Spike, the vampire with no soul who is reconciling himself to a life among the "stalwart and true" good guys [Giles in Buffy 2.07 "Lie to Me"]. In Buffy 6.08 "Tabula Rasa," we see Spike (as "Randy") stripped of all self-knowledge and awareness of himself as a vampire. On discovery of his vampire self, he intuitively identifies himself as on the side of good—"I must be a noble vampire. A good guy. On a mission of redemption"—leaping to the conclusion that he is, essentially, Angel.

"I help the helpless," he proclaims with pride, unconsciously echoing the motto of Angel Investigations. Contrast this with Marcus's behaviour: each man discovers that he inhabits the body of a vampire, but where Marcus's reaction is to embrace the evil, "Randy's" instinct is to reject it. It is significant that he does this without knowledge of his love for Buffy, or even of the chip that prevents him from hurting humans and proved the catalyst for these changes. It seems likely that this question of the nature of the vampire (or demon within) will be critical in future episodes of both Buffy and Angel this season. Buffy's Willow story arc is further evidence that good people may at times do bad things.

It is of note that these revelations, so integral to the major Buffy plot of Spike's reinvention, are not (at least at this stage) critical to the ongoing plot development in Angel. We need no convincing that Angel is a good guy—but how, when we contrast "Carpe Noctem" Marcus with "Tabula Rasa" Spike, can we fail to recognise that Spike is much more than the Serial-killer-in-prison analogy drawn by Mutant Enemy's David Fury during Season Five of Buffy.

If a soul is—as Whedon has suggested—an "inner moral compass" or guiding star [see http://www.cityofangel.com/behindTheScenes/bts/paley4.html], then Spike truly has no guiding light, except for, it has been suggested on numerous message boards, his love for Buffy, the superhero of the fight for good. [Note however that it has been proven many times over that Spike does good out of more than a simple desire to show Buffy that he can—most notably from Buffy 5.18 "Intervention" through the current season]. Yet somehow he still manages to do good, to transcend the vampire, just as Marcus lived down to the vampire in Angel's body.

When something changes, or a new situation is imposed on an old character, we must suppose it has meaning in the Buffyverse. Angel's training Cordelia to fight after all these years, with the attending observation (every week) that she may one day have to fight—and stake—his vampire self, parallels Buffy and Spike's very physical relationship. Indeed, in "Smashed" we see Buffy and Spike fighting one another, with the ironic twist that it is Buffy who is apparently "not right".

In the developing relationships of the shows' leading characters, we see another parallel theme. It is ironic that the final death-knell to Buffy and Angel's "eternal love" was dealt not by a staged meeting between them but by an off-camera rendezvous, dismissed afterwards by both as unimportant. Each of them returned to their own homes, to friends the other had never met, and to budding relationships only the most farsighted, imaginative and enthusiastic audience members could have foreseen when Angel left Buffy at the end of Buffy Season Three. ANGEL: "I've been thinking. About the future. And the more I do, the more I feel like us—you and me being together—is unfair to you." (from Buffy 3.20 "The Prom")

Angel and Buffy have moved on from their first love, both to relationships where one partner (in both cases the male) is more ready to admit his feelings, at least to himself. Each relationship is built on friendship and camaraderie, on physical and verbal sparring, and characterised by trust and honesty; we have already seen Cordelia's reaction when she feels Angel has not been honest with her, in her immediate transfer of sympathies to Darla. Presumably there will be a parallel in Buffy.

"Kye-rumption," explains Fred, to Angel (but really to the viewers) is a Pylean word describing the moment "when two great heroes meet on the field of battle and recognise their mutual fate". The word is applicable to both shows: if Cordelia and Angel have it, Buffy and Spike ooze it, even as early as Season Two:

SPIKE: I can't fight them alone and neither can you.
BUFFY: I hate you.
SPIKE: And I'm all you've got.
(from Buffy 2.22 "Becoming, Part Two")

Spoilers, rumours and publicity clips for future episodes also point to a further string of thematic crossovers. The lessons of Angel's Billy—that an innocent may be possessed by a demon—and the guilt that we see Wesley experience as a result of this—seem certain to be explored. These may also tie in with the persistent question on Buffy of what is "real", itself a more than ample subject for an essay.

Buffy 5.5 "Crush" XANDER (of Spike's feelings for Buffy): No, not creepy. 'Cuz it's not real.
Buffy 5.18 "Intervention" BUFFY: That thing [the Buffybot] ... it's not even real. What you did for me, and Dawn, that was real. And I'll never forget it.
Buffy 6.01 "Bargaining, Part One" TARA (repeated by the BuffyBot): The only really real Buffy is really ... Buffy
Buffy 6.07 "Once More with Feeling" BUFFY: Nothing here is real, nothing here is right.

So far, the themes have all been introduced on Angel and explored on Buffy. This suits the more episodic nature of Angel, and may also have been influenced by more pragmatic concerns. While the Angel "Fang Gang" is portrayed as a (for the most part) tightly knit group, the Scoobies in Buffy are being torn apart. The nature of the strong Buffy arc—and the need to follow the Scoobs as their lives are heading in different directions—leaves less time to introduce and explore these more complex issues. By running such a strong parallel between the two series, Mutant Enemy open the way for a more detailed and meaningful analysis of the characters' journey toward adulthood and maturity.

During Angel Season Two, we saw the disintegration and then rebuilding of the Fang Gang, as Angel questioned his identity and mission and the Gang their loyalty to him. Their re-formed relationships are stronger but different, and characterised by greater equality between the core characters—their investigations are no longer all about Angel.

Just as Angel's identity crisis led his friends to their own emotional coming of age, Giles's leaving will push the Scooby gang to redefine themselves. Giles believes that he is "standing in the way" of Buffy's maturity and ability to stand strong. His reasons for leaving are genuine, but his reasoning and attempt to resolve this by leaving leaves a lot to be desired. Perhaps Giles, too, has some growing up to do.

Buffy Season Six has echoed the Fang Gang's journey. As the Scoobies slowly pull apart, the Fang Gang pull together, with the ironic result that we may soon see Angel with a larger core group of friends than Buffy. The Fang Gang have already reached their emotional maturity, have deconstructed their relationships and found something that is worth nurturing, with recognition that each of them has a special place in the team. In "Fredless" (Angel 3.05), Fred explains to her parents that "Wesley is the brains, Cordelia is the heart, Gunn is the passion and Angel is the Champion." The Scoobies are still bound by their high-school friendships and shared experiences, but have little in common with one another these days.