Copied from http://www.theguitarguy.com/thiscoul.htm

THIS COULD BE THE START OF SOMETHING BIG
Words & Music by Steve Allen
Recorded by Steve Lawrence & Eydie Gorme, 1977*

 A7     Cdim      D   F#m   Bm       Bm7/E       Em7     G/B  A7
  You're walkin' along the street, or you're at a party,
  
     Cdim          G   G/F# Em7     Em6      Bm   Bm7/E
  Or else you're alone and then you suddenly dig,
  
          B7         G   G/F#  Em7       Em6      F#m Em7   B7
  You're looking' in someone's eyes, you suddenly re - al - ize
  
       G         G/F#    Em6      Gdim       D  Bm7   Em7
  That this could be the start of something big.
  
  
  A7     Cdim         D    F#m  Bm      Bm7/E        Em7   G/B  A7
  You're lunching at Twen - ty-One and watchin' your diet,
  
   Cdim         G    G/F#  Em7      Em6       Bm   Bm7/E
  Declining a char - lotte russe, accepting a fig,
  
        B7        G   G/F# Em7       Em6      F#m Em7  B7
  When out of a clear blue sky, it's suddenly gal and guy,
  
       G        G/F#    Em6      Gdim       D  Gdim   D
  And this could be the start of something big.
  
  
  
  Bridge:
  
         DM7    D7      Cdim   Am7    Cdim      D7       Am7      D9
  There's no controlling the unrolling of your fate, my friend,
  
     Cdim          Am7    Cdim     D7   Am7  D7  Am7  D9
  Who knows what's written in the mag - ic  book.
  
      D7     G     G/F#   Em    Em6     Bm            Bm7/E
  But when a lover you discover at the gate my friend,
  
      Bm7-5     E     E7     Em7  Bm7-5 A7
  In - vite her in without a sec - ond look.
  
  
  A7    Cdim       D   F#m   Bm       Bm7/E       Em7     G/B  A7
  You're up in an aer - o - plane or dining at Sardi's,
  
     Cdim     G    G/F# Em7  Em6         Bm   Bm7/E
  Or lying at Mal - i - bu alone on the sand,
  
      B7        G  G/F# Em7       Em6       F#m Em7  B7
  You suddenly hear a  bell, and right away you can tell
  
        G        G/F#    Em6      Edim       D
  That this could be the start of something grand.
  
  
  Bridge 2:
  
  
  D         Em7      F#m7    Edim      DM7       D6
  This could be the start of something very big,
  
      Cdim      G    G/F#  Em7
  Why don't you play your part?
  
  Em6     Gm       Edim Gdim  C C/B  Am7  Am7/G  A7
  Please give your heart to  me           and    see.
  
  D         Em7      F#m7    Edim      DM7       D6
  This could be the start of something wonderful,
  
      Cdim      G   G/F#  Em7
  Why don't you take a   chance?
  
  Em6  Gm     Edim Gdim  C C/B  Am7  Am7/G  A7
  Just try romance with  me          and    see.
  
  
   A7     Cdim         D  F#m  Bm     Bm7/E          Em7     G/B  A7
  You're watchin' the sun come up and countin' your money,
  
     Cdim      G   G/F# Em7        Em6      Bm   Bm7/E
  Or else in a dim caf - e  you're ordering wine,
  
       B7         G  G/F#  Em7         Em6      F#m  Em7  B7
  Then suddenly there he   is, and you wanna be where he is,
  
       G        G/F#    Em6     Gdim
  And this must be the start of something...
  
  F#m       C#m7-5     F#7      B7
  This could  be  the heart of something...
  
  G         G/F#    Em6      Gdim       D
  This could be the start of something big.

*The two introduced this song on The Tonight Show in the mid-50's when composer Allen was hosting it; they certainly recorded it earlier than the 1977 date I'm showing here, but I've been unable to pin down when their first recording was done, so this date will have to do for now.