Off the deep end

From Fresh Dictionary

English

Adjective

off the deep end

1. ((idiomatic{{#if:|, {{{2}}}{{#if:|, {{{3}}}{{#if:|, {{{4}}}{{#if:|, {{{5}}}{{#if:|, {{{6}}}{{#if:|, {{{7}}}{{#if:|, {{{8}}}{{#if:|, {{{9}}}}}}}}}}}}}}}}}}})) Crazy, erratic, or irrational.

   It used to be a funny comic, but lately it has gone off the deep end.

See also

• off the wall