Debut! And such a fun idea, a take on knock knock jokes. I enjoyed the puns, a surprise given that I'm sick of knock knock jokes (my two-year old constantly says "Interrupting cow MOO!"). My favorite was Sadie MAGIC WORD — "say the MAGIC WORD" — but the rest of them worked pretty well for me, too. I especially appreciated the multi-syllabic names, "Is there" punned upon as "Esther." "I want" as "Yvonne" was more of a stretch, but good puns are supposed to bad. Or something like that.
Love the audacity of a debut grid packed with six themers. Sometimes it's easier to work with six themers instead of five, as a longish (9+ letters) middle themer can create all sorts of problems.
Here, Brian does well to stack themers, WHOS THERE atop ANYONE HOME and I GET AN AMEN atop MA NO HANDS. This makes it more like you're working with four themers instead of six. As long as the overlapping letter pairs are friendly, this can make a constructor's life so much easier (vs. placing themers in every other row).
Brian had some flexibility in swapping themers, and he wisely paired up phrases resulting in such easy letter doublets like HA, EN, RY, EO at the top. The only one that's even remotely tricky is ??EO, but CLEO works fine there.
I'm usually happy to not notice short fill — its job is largely to stay out of the way — but TAXID is awfully nice. So hard to parse it into TAX ID.
HOB isn't as nice. Nor MLLES (although part of me does admire that crazy MLL beginning). Or ABED. But that's awfully good work from a debut constructor, especially considering the high theme density.
I would personally go out of my way to avoid ENSLAVE, as I prefer my crosswords to be uplifting, but to each his/her own.
Strong debut. I would have loved it if KNOCK KNOCK had been the first themer and WHOS THERE the second. Would also have been perfect if the themers had all related to knocking — [Esther] ANYONE HOME made for such an appropriate pun.