(;
AB[fn][dp][ep][fp][fq][gq][gr]
AW[cn][dq][eq][hq][er][fr]
C[White plays

Source:
    "Tesuji", James Davies]
(;
W[bq]
C[This kind of descent sometimes works, but not here.];
B[bp];W[bo];B[cq];W[cr];B[cp];W[ap]
C[And if White insists on trying to connect all the stones, ...];
B[br];W[aq];B[cs]
(;
W[ds]
C[Picnic ko for Black.]
)
    (;
    W[dr]
    C[Even worse.];
    B[fs]
    C[White's corner dies unconditionally.]
    )
)
    (;
    W[cp]
    C[Maybe this hane looks good, but White has a weakness.];
    B[co]
    C[The wedge tesuji exposes the defect in White's shape.]
    (;
    W[bq]
    C[White can save the corner, but ...];
    B[bo]
    C[... sealing in the corner is good for Black.]
    )
        (;
        W[bo]
        C[Of course, White might atari here, but ...];
        B[cq]
        C[... now White doesn't have a good response.];
        W[do]
        C[For example ...];
        B[bp]
        C[At best White has a heavy ko.  At worst, Black can also choose to simply capture the 4 lower side stones.]
        )
    )
    (;
    W[bp]
    C[The tesuji.]
    (;
    B[cp];W[bq]
    C[The reader can verify that Black cannot cut.]
    )
        (;
        B[cq]
        C[What does White do now?];
        W[cr]
        C[Correct.  Black still cannot cut.];
        B[bq]
        C[For example ...];
        W[cp]
        C[... Black has nothing.]
        )
    )
)

