Case file LinkedIn Crossclimb #792: 4-letter ladder, 5 middle exhibits, combo prompt "A compound word for something that keeps your place when reading a novel.". Endpoints: BOOK (top) and MARK (bottom).
Middle phase answers: "Sounds from a disappointed crowd" = BOOS; "___ and girls" = BOYS; "Coastal inlets (like those near San Francisco and Bengal)" = BAYS; "Soap units" = BARS; "The Red Planet (4th from the Sun)" = MARS.
Ordering phase: the valid middle chain is BOOS → BOYS → BAYS → BARS → MARS. This permutation is the only valid one-letter chain for these answers.
Evidence link: BOOK → BOOS. K→S at the fourth letter (BOOK → BOOS).
Evidence link: BOOS → BOYS. O→Y at the third letter (BOOS → BOYS).
Evidence link: BOYS → BAYS. O→A at the second letter (BOYS → BAYS).
Evidence link: BAYS → BARS. Y→R at the third letter (BAYS → BARS).
Evidence link: BARS → MARS. B→M at the first letter (BARS → MARS).
Evidence link: MARS → MARK. S→K at the fourth letter (MARS → MARK).
Verdict: BOOK → BOOS → BOYS → BAYS → BARS → MARS → MARK satisfies every one-letter constraint. The combo clue "A compound word for something that keeps your place when reading a novel." describes both end words together — "BOOK" and "MARK" each differ by one letter from their adjacent middle rungs and satisfy the shared top+bottom prompt.